1.  Pancreatic Injury Secondary to Blunt Trauma.  Philadelphia Annual Day of Trauma, Temple University Hospital, Philadelphia, Pennsylvania, October 11, 1986, Singer RL, Vernick JJ.

2.  Femoral Artery Pseudoaneurysms.  Resident Research Day, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania, May 21, 1988, Singer RL, Koniges F.

3.  Experience with Umbilical Artery Cutdowns in Neonates.  Resident Research Day, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania, May 20, 1989, Singer RL, Wolfson PJ.

4.  Major Airway Injuries.  Trauma Grand Rounds, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania, June 26, 1990, Singer RL.

5.   Update on Valve Surgery.  Cardiology Grand Rounds, Thomas Jefferson University Hospital, Philadelphia, Pennsylvania, March 4, 1992, Singer RL, Edie RN.

6.  Mitral Valve Repair.  Surgical Grand Rounds, Lehigh Valley Hospital, Allentown, Pennsylvania, April 14, 1992, Singer RL.

7.  Complications from Heparin-Induced Thrombocytopenia in Patients Undergoing Cardiopulmonary Bypass.  30^th Annual Meeting of the Pennsylvania Association for Thoracic Surgery, Nemacolin Woodlands, Pennsylvania, September 18, 1992, Singer RL, Mannion JD, Bauer TL, Armenti FR, Edie RN.

8.   Complications from Heparin-Induced Thrombocytopenia in Patients Undergoing Cardiopulmonary Bypass.  58^th Annual Scientific Assembly, American College of Chest Physicians, Chicago, Illinois, October 27, 1992, Singer RL, Mannion JD, Bauer RL, Armenti FR, Edie RN.

9.  Heart Smart Consumers.  Health Matters, WLVT Channel 39 Public Television, Allentown, Pennsylvania, November 12, 1992, Singer RL.

10.Operative Video-Assisted Thoracoscopy.  Symposium on Video-Assisted Thoracoscopy.  Lehigh Valley Hospital, Allentown, Pennsylvania, December 11, 1992, Singer RL, Kaiser LR.

11.Cardiothoracic Surgery as a Career.  Panel Discussion on Career Development and Placement.  Muhlenberg College, Allentown, Pennsylvania, November 3, 1993, Singer RL.

12.Thoracoscopic Surgery.  Surgical Grand Rounds.  Lehigh Valley Hospital, Allentown, Pennsylvania, November 23, 1993, Singer RL.

13. Medical Ethics.  Senior Scholar Symposium, Muhlenberg College, Allentown, Pennsylvania, November 29, 1993, Singer RL.

14. Health Care Reform.  National Public Radio, Los Angeles, California, December 9, 1993, Singer RL.

15. Thoracoscopic Surgery.  Medical Grand Rounds.  Lehigh Valley Hospital, Allentown, Pennsylvania, February 15, 1994, Singer RL.

16. Moderator, First Annual Update on Heart and Lung Surgery.  Regional Symposium Series.  Lehigh Valley Hospital, Allentown, Pennsylvania, March 26, 1994, Singer RL.

17. Surgery for Stage N2 Lung Cancer.  Oncology Grand Rounds.  Pottstown Memorial Hospital, Pottstown, Pennsylvania, August 17, 1994, Singer RL.

18. Cardiothoracic Surgery as a Career.  Panel Discussion on Career Development and Placement.  Muhlenberg College, Allentown, Pennsylvania, November 8, 1994, Singer RL.

19. Surgical Treatment of Lung Cancer.  Pulmonary Tumor Board.  Gnaden Huetten Memorial Hospital, Lehighton, Pennsylvania, November 17, 1994, Singer RL.

20. Moderator, Second Annual Update on Heart and Lung Surgery.  Regional Symposium Series.  Lehigh Valley Hospital, Allentown, Pennsylvania, March 25, 1995, Singer RL.

21. Surgery for Advanced Lung Cancer.  Second Annual Update on Heart and Lung Surgery.  Regional Symposium Series.  Lehigh Valley Hospital, Allentown, Pennsylvania, March 25, 1995, Singer RL.

22. Heparin-Induced Thrombocytopenia in Patients Undergoing Cardiopulmonary Bypass.  Mechanisms of Perfusion X.  San Francisco, California, May 14, 1995, Singer RL.

23. Video-Assisted Thoracoscopy.  Association of Surgical Technologists, Local Chapter 290.  Lehigh Valley Hospital, Allentown, Pennsylvania, September 6, 1995, Singer RL.

24. Choosing a Physician:  The Politics of Healthcare in the 90’s.  Emmaus Rotary Club Meeting.  Merchantile Club, Emmaus, Pennsylvania, September 21, 1995, Singer RL.

25. Advances in Thoracoscopic Surgery.  Lehigh Valley Health Information Management Association Meeting.  Lehigh Valley Hospital, Allentown, Pennsylvania, January 23, 1996, Singer RL.

26. Heparin-Induced Thrombocytopenia in the Cardiac Patient.  Medical Grand Rounds.  Lehigh Valley Hospital, Allentown, Pennsylvania, February 20, 1996, Singer RL.

27. Advances in Video-Assisted Thoracoscopy.  Mid-Eastern Pennsylvania Chapter AORN Guest Lecturer.  Lehigh Valley Hospital, Allentown, Pennsylvania,  March 12, 1996, Singer RL.

28. Moderator, Third Annual Update on Heart and Lung Surgery.  Regional Symposium Series.  Lehigh Valley Hospital, Allentown, Pennsylvania, March 23, 1996, Singer RL.

29. Congenital Heart Anomalies and Surgical Corrections.  Invasive Cardiology RCVT Review Course.  Lehigh Valley Hospital, Allentown, Pennsylvania, August 3, 1996, Singer RL.

30. Minimally Invasive Cardiac Surgery.  Ninth Annual Cardiovascular Nursing Seminar.  Lehigh Valley Hospital, Allentown, Pennsylvania, September 18, 1996, Singer RL.

31. Minimally Invasive Cardiac Surgery.  Surgical Grand Rounds.  Lehigh Valley Hospital, Allentown, Pennsylvania, October 1, 1996, Singer RL.

32. Minimally Invasive Cardiac Surgery.  Association of Surgical Technologists, Chapter 290.  Lehigh Valley Hospital, Allentown, Pennsylvania, December 4, 1996, Singer RL.

33. Minimally Invasive Cardiac Surgery: An Overview and Introduction to Heartport (Port-Access Coronary Artery Bypass & Valve Surgery), Zipper Club, Lehigh Valley Hospital, Allentown, Pennsylvania, March 12, 1997, Singer RL.

34. Moderator, Fourth Annual Update on Heart and Lung Surgery.  Regional Symposium Series.  Lehigh Valley Hospital, Allentown, Pennsylvania, April 12, 1997, Singer RL.

35. Minimally Invasive Cardiac Surgery: An Overview and Introduction to Heartport (Port-Access Coronary Artery Bypass & Valve Surgery), Fourth Annual Update on Heart and Lung Surgery, Regional Symposium Series, Lehigh Valley Hospital, Allentown, Pennsylvania, April 12, 1997, Singer RL.

36. Minimally Invasive Cardiac Surgery: An Overview and Introduction to Heartport (Port-Access Coronary Artery Bypass & Valve Surgery), Board of Associates Meeting, Lehigh Valley Hospital, Allentown, Pennsylvania, April 16, 1997, Singer RL.

37. Minimally Invasive Cardiac Surgery:  An Overview and Introduction to Heartport (Port-Access Coronary Artery Bypass & Valve Surgery), Medical Grand Rounds, Lehigh Valley Hospital, Allentown, Pennsylvania, June 10, 1997, Singer RL.

38. Adverse Effects of Smoking.  Lifetime Physical Fitness & Wellness Lecture Series.  Muhlenberg College, Allentown, Pennsylvania, October 29, 1997, Singer RL.

39. New Techniques in Cardiac Surgery.  Leonard Pool Society Fall Event.  Lehigh Valley Hospital, Allentown, Pennsylvania, October 29, 1997, Singer RL.

40. New Staging System for Lung Cancer.  Lung Tumor Board.  John and Dorothy Morgan Cancer Center, Lehigh Valley Hospital, Allentown, Pennsylvania, November 12, 1997, Singer RL.

41. Adverse Effects of Smoking.  Lifetime Physical Fitness & Wellness Lecture Series.  Muhlenberg College, Allentown, Pennsylvania, March 26, 1998, Singer RL.

42. Moderator, Fifth Annual Update on Heart and Lung Surgery.  Regional Symposium Series.  Lehigh Valley Hospital, Allentown, Pennsylvania, March 28, 1998,  

     Singer RL.

43. Minimally Invasive Cardiac Surgery.  Lehigh Valley Health Information Management Association Regional Meeting.  Lehigh Valley Hospital, Allentown, Pennsylvania, April 7, 1998, Singer RL.

44. Surgical Treatment of Limited Small-Cell Lung Cancer.  Lung Tumor Board.  John and Dorothy Morgan Cancer Center, Lehigh Valley Hospital, Allentown, Pennsylvania, April 22, 1998, Singer RL.

45. Choosing a Physician or Hospital:  The Politics of Healthcare in the 90’s.  Zipper Club, Lehigh Valley Hospital, Allentown, Pennsylvania, June 11, 1998, Singer RL.

46. Transmyocardial Laser Revascularization.  Surgery Grand Rounds, Lehigh Valley Hospital, Allentown, Pennsylvania, September 29, 1998, Singer RL.

47. Update on Latest Advances in Cardiothoracic Surgery.  Cardiology Journal Club, North Penn Memorial Hospital, Lansdale, Pennsylvania, December 11, 1998, Singer RL.

48. Moderator.  Sixth Annual Update on Heart and Lung Surgery.  New approaches for the next frontier in cardiothoracic surgery.  Lehigh Valley Hospital and Penn State University College of Medicine, Allentown, Pennsylvania, April 10, 1999, Singer RL.

49. Three-year follow-up on two patients with cardiac rupture secondary to acute transmural myocardial infarction treated successfully with cyanoacrylate glue without cardiopulmonary bypass.  The Pennsylvania Association for Thoracic Surgery, 37^th Annual Meeting, Skytop Lodge, Skytop, Pennsylvania, September 18, 1999, Singer RL.

50. Moderator.  Seventh Annual Update on Heart and Lung Surgery.  Lehigh Valley Hospital and Penn State University College of Medicine, Allentown, Pennsylvania, April 15, 2000, Singer RL.

51. Moderator.  Indications and Techniques for Homograft, Autograft and Stentless Aortic Valve Replacement.  CryoLifeâ, Inc. Conference.  Glasbern Inn, Fogelsville, Pennsylvania, July 18, 2000, Singer RL.

52. New Technologies in Cardiothoracic Surgery.  Nursing Education Seminar. Lehigh Valley Hospital, Allentown, Pennsylvania, August 29, 2000, Singer RL.

53. New Technologies and Clinical Investigations in the Division of Cardiothoracic Surgery at Lehigh Valley Hospital.  Presentation to Senior Management and the Board of Trustees, Lehigh Valley Hospital, Allentown, Pennsylvania, September 13, 2000, Singer RL.

54. Routine Right Axillary Artery Cannulation for Repair of Type A Aortic Dissection:  Case Report and Illustration of Technique.  The Pennsylvania Association for Thoracic Surgery, 38^th Annual Meeting, Southampton Princess, Bermuda, October 5, 2000, Singer RL.

55. Moderator, Scientific Session.  The Pennsylvania Association for Thoracic Surgery, 38^th Annual Meeting, Southampton Princess, Bermuda, October 7, 2000, Singer RL.

56. The Art and Practice of Cardiothoracic Surgery.  Guest Lecturer. Cedar Crest College, Allentown, Pennsylvania, October 31, 2000, Singer RL.

57. Traumatic Injuries of the Aorta.  Trauma 2001: A Continuum of Care.  Sponsored by the Lehigh Valley Hospital Trauma Division.  Holiday Inn, Route 100 & I-78, Fogelsville, Pennsylvania, March 8, 2001, Singer RL.

58. Moderator and Course Director.  Innovations in Cardiac Care:  A Symposium for Physicians and Nurses.  Sponsored by the Regional Heart Center of Lehigh Valley Hospital.  April 28, 2001.  Singer RL.

59. Overview of New Technologies in Cardiac Surgery.  Innovations in Cardiac Care:  A Symposium for Physicians and Nurses.  Sponsored by the Regional Heart Center of Lehigh Valley Hospital.  April 28, 2001. Singer RL.

60. Review of Cardiac and General Thoracic Surgery.  Guest Lecturer.  Operating Room Student Training Course.  Lehigh Valley Hospital.  September 18, 2001.  Singer RL.

61. The Art and Practice of Cardiothoracic Surgery.  Guest Lecturer.  Cedar Crest College, Allentown, Pennsylvania, October 30, 2001. Singer RL.

62. Aortic Trauma.  Guest Lecturer, Operating Room.  Lehigh Valley Hospital, Allentown, Pennsylvania, November 27, 2001. Singer RL.

63. Aortic Trauma.  Guest Lecturer, Open Heart and Transitional Open Heart Units.  Lehigh Valley Hospital, Allentown, Pennsylvania, December 18, 2001.  Singer RL.

64. New Technologies in Cardiothoracic Surgery.  Medical Grand Rounds.  Hunderton Medical Center, Flemington, New Jersey, February 20, 2002.  Singer RL.

65. Moderator and Course Director.  Second Annual Innovations in Cardiac Care:  A Symposium for Physicians and Nurses.  Sponsored by the Regional Heart Center of Lehigh Valley Hospital and Health Network.  May 4, 2002.  Singer RL.

66. New Technologies in Cardiothoracic Surgery.  Medical Grand Rounds.  Pottstown Memorial Hospital, Pottstown, Pennsylvania, September 18, 2002. Singer RL.

67.  New Technologies in Cardiothoracic Surgery.  Family Practice Grand Rounds.  Lehigh Valley Hospital, Allentown, Pennsylvania.  October 1, 2002.  Singer RL

68. Ethics and New Technologies in Cardiothoracic Surgery.  Guest Lecturer.  Moravian College, Bethlehem, Pennsylvania.  November 18, 2002.  Singer RL.

69. Latest Advances in Cardiothoracic Surgery and Interventional Cardiology.  Gnaden Huetten Memorial Hospital, Lehighton, Pennsylvania.  February 12, 2003.  Kleaveland JP, Szydlowski GW, Singer RL.

70. Late prosthetic mechanical aortic valve conduit endocarditis after repair of Type A aortic dissection.  41^st Annual Meeting, The Pennsylvania Association for Thoracic Surgery, The Geisinger Medical Center, Danville, Pennsylvania.  October 4, 2003.  Singer RL, Szydlowski GW.

71. Missile embolism to the pulmonary artery: Case report and pitfalls of management. 41^st Annual Meeting, The Pennsylvania Association for Thoracic Surgery, The Geisinger Medical Center, Danville, Pennsylvania.  October 5, 2003. Singer RL, Szydlowski GW.

72. Moderator. Cardiovascular Disease: State of the Art.  The Heart Care Group First Annual Symposium, The Glasbern Inn Conference Center, Fogelsville, Pennsylvania.  November 15, 2003.  Singer RL.

73. Update on New Technologies in Cardiothoracic Surgery.  The Cardiac Update Physician Program.  The Heart Care Group.  The Oak Hill Inn, Orwigsburg, Pennsylvania.  February 24, 2004.  Singer RL.

74. New Technologies in Cardiothoracic Surgery.  The Cardiac Update Physician Program.  The Heart Care Group.  The Library Restaurant, Hazleton, Pennsylvania.  March 31, 2004.  Singer RL.

75. Constrictive pericarditis presenting as an anterior mediastinal mass complicated by a chylous effusion:  Case report and discussion of the elusive diagnosis of constrictive pericarditis.  42^nd Annual Meeting of The Pennsylvania Association for Thoracic Surgery.  October 9, 2004.  Harrison TD, Singer RL.

76. Lung Cancer 2004:  Practical Practice Guidelines.  The Lodge, Reeders, Pennsylvania.  November 18, 2004, Singer RL.

77. Chest Tubes.  Grand Rounds Lecture, Department of Emergency Medicine, Lehigh Valley Hospital, Muhlenberg Campus, Bethlehem, Pennsylvania.  February 24, 2005, Singer RL.

78. Moderator. Lehigh Valley Hospital Update on Heart and Lung Surgery Symposium.  Lehigh Valley Hospital, Allentown, Pennsylvania. March 19, 2005, Singer RL.

79. Review of Cardiothoracic Surgical Procedures and Techniques.  OR Student Nurse Lecture Series, Lehigh Valley Hospital, Allentown, Pennsylvania, September 22, 2005, Singer, RL.

80. Pneumocephalus as a complication of pulmonary resection: case report and review of the literature.  43^rd Annual Meeting of The Pennsylvania Association for Thoracic Surgery, Elbow Beach Resort, Paget Parish, Bermuda, October 1, 2005, Singer, RL.

81. New Technologies in Cardiothoracic Surgery.  AORN Lecture Series.  The Association for Peri-Operative Nursing Meeting, Lehigh Valley Hospital, Allentown, Pennsylvania, January 10, 2006, Singer, RL.

82. Lung Cancer 2007: Practical Practice Guidelines.  Multi-Disciplinary Lung Cancer Tumor Board Conference.  Hunderton Medical Center, September 11, 2006, Singer, RL.

83. The Future of Cardiothoracic Surgery: 2007 and Beyond.  Grand Rounds Lecture. Hunderton Medical Center, Flemington, New Jersey, September 27, 2006, Singer, RL.

84. Program Chair and Moderator.  The 44^th Annual Meeting of The Pennsylvania Association for Thoracic Surgery, Lehigh Valley Hospital, Allentown, Pennsylvania, September 29-October 1, 2006, Singer, RL.

85. Mitral Valve Surgery in Women.  Heart Help for Women Seminar. Lehigh Valley Hospital, Allentown, Pennsylvania, February 2, 2007, Singer, RL.

86. The Future of Cardiothoracic Surgery: 2007 and Beyond.  Third Annual Advances in Cardiac Care Symposium.  Best Western Conference Center, Bethlehem, Pennsylvania; Supported by the Regional Heart Center, Lehigh Valley Hospital and Health Network, Allentown, Pennsylvania, February 8, 2007, Singer, RL.

87. The Future of Cardiothoracic Surgery: 2007 and Beyond.  General Membership Meeting, The Lehigh County Medical Society, Allentown, Pennsylvania, February 20, 2007, Singer RL.

88. Aortic Disease: Diagnosis and Treatment of Acute Aortic Dissection.  Morbidity and Mortality Continuing Medical Education Conference.  Guest Lecturer.  Grand View Hospital, Sellersville, Pennsylvania, April 11, 2007, Singer RL.

89. Pay for Performance: The Train Has Left The Station. 45^th Annual Meeting, The Pennsylvania Association for Thoracic Surgery, East Sea View Resort, Atlantic City, New Jersey, October 12, 2007, Singer RL.

90. Subtle Acute Traumatic Aortic Injury: Outcomes of Non-Operative Management, Abstract and Poster Presentation, Summit on Acute Aortic Diseases: Lux et Veritas, Yale University Medical School, November 1-2, 2007, Wu JK, Phillips TG, Singer RL, Szwerc MF, Pasquale MD, Szydlowski GW.

91. Pay for Performance: The Train Has Left the Station. Guest Lecturer, General Membership Meeting, The Lehigh County Medical Society, Allentown, Pennsylvania, April 8, 2008, Singer RL.

92. Coronary Artery Bypass Surgery—Still the Best Treatment for Multi-Vessel and Left Main Disease, The Heart Care Group 5^th Annual State of The Art Symposium, Lehigh Country Club, Allentown, Pennsylvania, April 12, 2008, Singer RL.

93. Coronary Artery Bypass Surgery Using Conventional Techniques Continues to Provide Quality Outcomes: A 5-Year Retrospective Review of 2,333 Consecutive Cases at a Single Institution.  46^th Annual Meeting of The Pennsylvania Association for Thoracic Surgery, Amelia Island Plantation, Amelia Island, Florida, October 3, 2008, Singer RL.

94. Coronary Artery Bypass Surgery Using Conventional Techniques Continues to Provide Quality Outcomes: A 5-Year Retrospective Review of 2,333 Consecutive Cases at a Single Institution.  3^rd Annual Hazelton Cardiovascular Update, Hazelton, Pennsylvania, December 2, 2008, Singer RL.

95. The Preservation of Youth Revisited: What Maimonides Teaches Us About Heart Health Today.  Guest Speaker, 3^rd Annual Healthy Feast, The Maimonides Society of the Jewish Federation of the Lehigh Valley and Congregation Sons of Israel.  Congregation Sons of Israel Synagogue, Allentown, Pennsylvania, January 11, 2009, Singer RL.

96. Coronary Artery Bypass Surgery Using Conventional Techniques Continues to Provide Quality Outcomes: A 5-Year Retrospective Review of 2,333 Consecutive Cases at a Single Institution.  Guest Lecturer, Division of Cardiology, Lehigh Valley Health Network, Allentown, Pennsylvania, January 13, 2009, Singer RL.

97. My Aging Heart. Penn State Lehigh Valley SAGE Lecture (Senior Adults Gaining Enrichment), Penn State Lehigh Valley Corporate Learning Center, 100 Brodhead Road, Suite 120, Bethlehem, Pennsylvania, April 3, 2009, Singer RL.

98. Contemporary Treatment Options for Valvular Heart Disease.  Symposium Director and Moderator. Regional Heart Center, Lehigh Valley Health Network, Allentown, Pennsylvania, September 23, 2009, Singer RL.

99. Carcinoid Tumors of the Lung –Evaluation, Surgical Resection and Intermediate Term Analysis.  The Pennsylvania Association for Thoracic Surgery, 48^th Annual Meeting, Ritz Carlton Convention Center, Amelia Island, Florida, October 9, 2009, Singer RL.

100. Negotiating Your First Contract.  Essential Skills for Surgical Practice: A Primer for Residents.  American College of Surgeons, 95^th Annual Clinical Congress.  Chicago, Illinois, October 12, 2009, Singer, RL.

101. Valve Surgery –Past, Present, and Future.  Surgery Grand Rounds Lecture.  Lehigh Valley Health Network, December 1, 2009, Singer RL.

102. Valve Surgery –Past, Present, and Future.  CVT-Cardiovascular Therapeutics: Patient Care in the Era of Health Care Reform.  Lehigh Valley Health Network, March 6, 2010, Singer RL.

103. Live Television Interview on Barbara Walter’s Valve Surgery.  The Sunrise Show with Eve Tannery.  WFMZ Channel 69 News.  May 13, 2010, Singer RL.

104. Valve Surgery –Conventional, Minimally Invasive, and Percutaneous Technologies.  1^st Annual Update: Contemporary Advances in Cardiovascular Services.  Schuylkill Health System, May 19, 2010, Singer RL.

105. Understanding Valve Surgery: What you and your family need to know.  ABC’s of Heart Valve Surgery.  Community Event.  Lehigh Valley Health Network, May 25, 2010, Singer RL.

106. Valve Surgery –Conventional, Minimally Invasive, and Percutaneous Technologies. 2^nd Annual Update: Contemporary Advances in Cardiovascular Services.  Blue Mountain Health System.  May 27, 2010, Singer RL.

107. Valve Surgery –Past, Present, and Future.  Cardiology Grand Rounds Lecture. Lehigh Valley Health Network, June 4, 2010, Singer RL.

108. Valve Surgery --Past, Present, and Future. Medical Grand Rounds Lecture. Hunterdon Medical Center, Flemington, New Jersey, January 19, 2011, Singer RL.

109. Valve Surgery --Past, Present, and Future. Lehigh Valley Anesthesia Services Winter Retreat Conference. Bear Creek Lodge, Macungie, Pennsylvania, January 22, 2011, Singer RL.

110. Valve Surgery --Past, Present, and Future. Lehigh Valley Anesthesia Services Winter Retreat. Bear Creek Mountain Resort, Macungie, Pennsylvania, January 22, 2011, Singer, RL.

111. Percutaneous Valves: A New Paradigm in the Management of Patients with Advanced Heart Valve Disease, Update in Cardiology 2011, Lehigh Valley Health Network, Allentown, Pennsylvania, March 5, 2011, Singer RL.

112. What You Need to Know About Heart Valve Surgery. Community Event, Board of Trustees Development Committee, Lehigh Valley Health Network, Allentown, Pennsylvania, October 13, 2011, Singer RL.

113. Valve Surgery --Past, Present, and Future. What's New In Cardiology. The Heart Care Group Annual Symposium. Lehigh Country Club, Allentown, Pennsylvania, October 15, 2011, Singer RL.

114. Negotiating Your First Contract. Essential Skills for Surgical Practice: A Primer for Residents. The American College of Surgeons 97th Annual Clinical Congress, San Francisco, California, October 24, 2011, Singer RL.