Brian Smith submitted his resignation this week as the town representative on the Martha’s Vineyard Commission.

“I thank you for the opportunity to serve West Tisbury on the MVC for the last four years,” Mr. Smith wrote in a letter to the selectmen Sept. 4.

At their meeting Wednesday, selectmen expressed open dismay at the news. “I can’t believe it,” said board chairman Jeffrey (Skipper) Manter 3rd.

“He’s gone way beyond what we’ve expected him to do,” selectman Richard Knabel said.

Since he was first appointed in 2010, Mr. Smith has played a quiet leadership role on the commission where he served as clerk-treasurer and presided over development of regional impact hearings, including the recent series of long-running public hearings on the Stop & Shop expansion plans. In 2013 when the commission came under fire for increases in its budget, Mr. Smith defended the commission’s fiscal responsibility and role as a regional planning agency.

Now he needs more time for his business and personal life, he told the selectmen in his letter. “I have business and personal commitments . . . I need to read more Dr. Seuss and less zoning regulations,” he wrote. “When the time is right, I’ll be back.”

The board voted to accept Mr. Smith’s resignation with “deep regret and gratitude,” and said they will advertise for someone to take his place.

Mr. Smith’s departure marks one of two recent resignations from the commission. Last week the Tisbury selectmen appointed Harold Chapdelaine to replace Ned Orleans as their town representative to the MVC. Mr. Orleans had also been active on the commission as well as the Tisbury planning board.

The 21-member commission includes nine members who are elected at large every two years and one appointed member from each Island town and the county. All have voting power. There are also four governor’s appointed members, one with voting power.