Elmer William Ellsworth, longtime convention manager for AAPG, passed away at his home in San Francisco on September 22, 1997, at age 90. Known to his many friends in geological circles as "Lefty," he will be remembered not only as one of the true builders of AAPG, but also as a devoted family man, a cheerful coworker, and an unwavering believer in God, country, and community. Ellsworth was born in Norfolk, Virginia on June 17, 1907, but was raised in Madison, Wisconsin. An energetic student, he attended Draper School and was the valedictorian of his class at University High School. An enthusiastic young outdoorsman, he became Madison's second Eagle Scout. Entering the University of Wisconsin in the fall of 1925, Lefty was at first undecided upon a major, but a strong affinity for coursework in geology, along with three summers of fieldwork for the Wisconsin State Geological Survey, set the course of his professional career. Selected as a U. W. Scholar in Geology, he took his B.A. degree in 1929 and his M.A. degree one year later. In 1930, Ellsworth headed west to commence his doctoral studies in geology at Stanford University. Working under the direction of Elliott Blackwelder, he undertook fieldwork in the Mojave Desert, where he traced the history of Pleistocene lakes in the Afton Basin. While a student at Stanford, Lefty also worked for Pickands, Mather and Company, conducting a geomagnetic survey of Michigan iron ore deposits under the guidance of C. K. Leith. Upon receiving his Ph.D. from Stanford in 1933, Ellsworth served as the West Coast representative for W. C. McBride, Inc., a St. Louis consulting firm. Specializing in the use of the powerful Hotchkiss superdip magnetometer, Lefty subsequently conducted geomagnetic surveys for the U.S. Geological Survey, for whom he appraised tin deposits in Alabama, and for the Electro Geometer Corporation, exploring for oil structures in Florida and Alabama. He returned to W. C. McBride in 1935. Working under the supervision of Noel H. Stearn, Ellsworth conducted surface and subsurface exploration for petroleum in Oklahoma, Kansas, Texas, Mississippi, Indiana, and, particularly, Illinois, where the Centralia oil boom was in full swing. Moving to Centralia in 1938, Lefty soon set out on his own as a consulting geologist. Serving as the executive secretary for the Independent Oil Producers Association of Illinois, he also created the Electrical Log Well Bureau, a non-profit, cooperative organization. The centerpiece of the Bureau was its well log library, which contained thousands of electrical logs from more than 300 Illinois basin operatives. With the outbreak of World War II, Ellsworth joined the U.S. Army Air Corps as an intelligence officer. Owing to his familiarity with desert conditions, he was assigned to the Arctic, Desert, and Tropic Information Service, which created survival manuals for allied airmen shot down over hazardous terrain. While he was stationed in New York City, a pretty young secretary in the office, Helen K. Solberg of Minneapolis, caught his eye. They married in 1946 but did not set up housekeeping until after the conclusion of Lefty's active military service. Upon the cessation of hostilities in August 1945, Lefty, now an Air Force major, was sent to the Far East as part of the occupation of Japan. Assigned to Gen. Douglas MacArthur's staff in Tokyo as a technical advisor in the natural resources section, he assessed the conditions of mines and fisheries in Japan and Korea, counseled Japanese scientists on their technical needs, and helped determine scientific research policy for the occupation government. In addition, Lefty also helped reorganize the Boy Scouts of Japan, for which he later received the Silver Medal from the Japanese Scouts. Following his return to civilian life during the summer of 1946, Lefty and his bride moved to Tulsa, where he joined the then miniscule staff of AAPG as assistant business manager. Lefty and Helen raised their three children in Tulsa, and were faithful members of the First Presbyterian Church. In 1952, he was promoted to business manager at AAPG. Early on in his career at AAPG, Ellsworth also took on the position of convention manager. Throwing himself into the job with characteristic verve and careful attention to detail, Lefty virtually revolutionized the management of AAPG conventions, widening their scope, streamlining operations, reorganizing committee work, and elevating their importance within the petroleum industry. Over the course of a quarter of a century, with Helen often at his side, Lefty managed AAPG conventions and meetings in more than 30 cities across North America. Along the way, he also became a nationally recognized authority on convention management. His AAPG Convention Manual, with its timelines, checklists, and novel methodology for estimating attendance, was widely praised in trade publications, while he served as an unofficial ambassador of goodwill for AAPG within the national association community. In 1961, Ellsworth was awarded the Chartered Association Executive Award by the American Society of Association Executives. After 25 years at AAPG headquarters, Lefty retired in the spring of 1972. Elected to honorary membership in AAPG and as a fellow in the Geological Society of America, he was subsequently presented with the Distinguished Service Award by SEPM. Lefty and Helen, meanwhile, moved to San Francisco, where he worked briefly as an independent convention management consultant, notably with the first Circum-Pacific Energy and Mineral Resources Conference. His primary passion was the jail ministry program he created, which won the praise not only of local officials, but also of Norman Vincent Peale and other theologians. After a long struggle with Alzheimer's, Lefty passed away at home, in peace. Ellsworth is survived by his wife, Helen, of San Francisco; two sons, William, of Menlo Park, California, and Scott, of Portland, Oregon; a daughter, Constance, of San Francisco; and four grandchildren. A member of AAPG since 1936, Lefty was deeply proud of the association, its growth, and its accomplishments. A loving husband and father, he will be remembered by coworkers and associates alike for his steady professionalism, his buoyant optimism, and, perhaps above all, his unfailing courtesy.