Alan Rush Willens died peacefully on Monday, March 14 with his family at his side. He was 80 and had determinedly battled cancer for many years, characteristically charting the battle with an excel spread sheet.

He was born Jan. 14, 1936, in Detroit, Mich. He received a bachelor of business administration in 1957 and a master of business administration in 1958 from the University Michigan.

In 1965, with two friends, he started a research company, CRA. Their first offices were a two-bedroom suite in the Sheraton Commander Hotel in Cambridge. The company grew steadily and eventually occupied two floors on the Hancock Tower in Boston. CRA is now an international company that recently celebrated its 50th anniversary.

He was the oldest of three children. His love of the water and of sailing started young with family sailing trips. Alan sailed to Martha’s Vineyard many times. In the spring of 1998, he and his life partner, el edwards, enjoyed a week-long stay on the Island, compliments of a family member. By the end of that visit, Alan had arranged a summer rental. By the end of that rental, Alan had decided the Island would be his home. As luck would have it, he rented a house in Harthaven. “We knew almost immediately that we had found the place we wanted to live for the rest of our lives,” recalled el. “We were drawn to the nearby beach, the harbor where Alan could keep a boat but most importantly to the sense of community we felt there.” In the summer of 1999, the couple started building their own home in Harthaven.

Alan may have retired from CRA, but on the Vineyard he stayed busy, actively participating in a number of community and nonprofit organizations — the Martha’s Vineyard Hospital, the Film Society and more. He also became a personal computer guru to friends, neighbors and family on a strictly amateur basis.

The Harthaven beach called to Alan. He walked it almost every day in weather fair and foul and could be seen carrying out trash left behind by careless visitors. From these daily walks he created an impressive collection of sea glass. An accomplished photographer, he documented the arrival, courtship, family feuds and departure of Harthaven’s ospreys, which he published in the community newspaper, the Harthaven Herald.

“Alan was an extremely kind soul,” said Harthaven resident Peggy (Moore) Yoars. “When he learned that our trusty vehicle had died after a long and arduous life, he gave us a car. You need it more than we do, he told us. We will always be grateful to him. We miss him terribly.”

Alan was a special person. He had a deep sense of responsibility to his family, to his friends, and to his community. Martha’s Vineyard was where he was the happiest. The longer he lived here the less he wanted to leave. Even a quick visit to Boston would have him pushing to get back to the Island. Harthaven was home and his neighbors were truly family to him.

He is survived by el and his daughters, Beth Rose Willens of San Rafael, Calif., and Lori Willens, of Bend, Ore.; his son Scott Willens of San Anselmo, Calif.; his sister Kathy Willens of Brooklyn, N.Y. and five grandchildren, Max Sinclair of Portland, Ore.; Dylan Hollander of Tampa, Fla.; Grace and Reid Willens of San Anselmo, Calif. and Oliver Stoefen of Bend, Ore.

In lieu of flowers donations can be made to the Martha’s Vineyard Hospital.