From their earliest days, they did good works, and had fun doing them.

The first money they raised, from an informal series of summer square dances, went to Martha’s Vineyard Hospital.

Over the decades, the people and organizations who have been helped by their efforts include Vineyard high school graduates, Hospice of Martha’s Vineyard, the Oak Bluffs Public Library, the National Association for the Advancement of Colored People, the Food Pantry, Windemere Nursing Home and Martha’s Vineyard Community Services.

Many of them live most of the year off-Island. Yet it is on the Vineyard, and with each other, that they often have found their truest community.

They are the Cottagers. At 4 p.m. Sunday in Union Chapel on Kennebec avenue in Oak Bluffs, they will mark their 50th anniversary with a public program of music, talks and awards, followed by a reception on the chapel grounds.

Sunday’s program is one of a series of both public and invitation-only events planned for this summer by the group, a club of African-American women whose legacy of service to the Island stretches back even past their official founding in 1956.

The Cottagers want to ensure that their tradition of service continues in the coming decades.

The goal, club president Thelma Hurd said this week, “is to continue the legacy of our founders, to build on that, and not to build on it so that what they originally founded is not recognizable, but to leave the footprints that they left and made on the sands of time forever on this Island.”

On Tuesday afternoon, six Cottagers gathered on the wide front porch of Bettye Foster Baker’s house on Canonicus avenue in Oak Bluffs to talk about the group.

Besides Ms. Baker and Ms. Hurd, they included Sheila Platt, Rosemarie Davis, Mycki Jennings and Myrna Allston.

Their mainland homes are up to hundreds of miles away from the Island. Ms. Platt is from Warren, N.J., Ms. Davis from Westchester County, N.Y., Ms. Jennings from New Haven, Conn., Ms. Allston from Boston, and Ms. Hurd from Elizabeth, N.J.

Some of the Cottagers, such as Ms. Hurd and Ms. Allston, learned first-hand about the group as girls and young women when older Cottagers would bring them to club events.

Others, such as Ms. Davis, were proselytized by members off-Island during the off-season. A Cottager who was a neighbor of Ms. Davis’s in Brooklyn would keep after her to join.

For Ms. Platt, the Cottagers have helped provide the kind of community she hasn’t found anywhere else.

“There is a wonderful feeling to be part of the community,” she said.

For Ms. Jennings, the Cottagers have provided a way to give back to the community, and to tap Cottager connections to make improvements in her mainland community, reducing the six degrees of separation to “maybe three or four degrees.”

It’s not all work in the Cottagers. Members get together to play golf at Farm Neck, for tennis and for bridge. Cottagers also have been known to get involved with other Vineyard groups. Ms. Allston is a member of the Polar Bears, who mix Monday morning dips in the ocean off Sea View avenue with an extensive outdoor smorgasbord to bring back their strength.

The Cottagers’ roots date back to at least the early 1940s in Oak Bluffs, to a group of 12 or 14 women who used to get together when they summered on the Vineyard.

One summer, they decided to throw a series of square dances at the Shearer cottage in Oak Bluffs, the first inn on the Vineyard owned by and catering to blacks. The cottage was owned by the grandparents of Liz White, who was living there at the time.

The group charged dancers $1 a head, and turned the proceeds over to Martha’s Vineyard Hospital.

The dances were so successful that the women decided to form a club to raise money for Vineyard charities.

Hence the founding of the Cottagers, whose membership required the ownership of a cottage in Oak Bluffs.

Initially club membership was limited to 40. By the early 1960s, the club had expanded to slightly over 50 members. At present, membership is limited to 100. Applicants are waiting to get in.

Headquarters for the Cottagers is Cottages Corner, a former Oak Bluffs town hall, at 57 Pequot avenue.

Ms. White and famed writer Dorothy West, founding members of the club, were among those who advocated the purchase of the property, previously bought from the town by a private individual.

A number of members wondered what a summer club would do with a year-round building. One answer: provide a space for young people to come in the off-season, which the Cottagers proceeded to do.

The Cottagers bought the property in 1968. Nine years later, they sold another piece of property that they owned on Wamsutta avenue to the town for a council on aging building, and used the proceeds to retire the mortgage on Cottagers Corner.

Since last year, the Cottagers have been planning this summer’s series of events to mark the club’s 50th anniversary in style.

Events that already have taken place include the African-American Cultural Fair in late July, and the club’s annual fashion show, which was scheduled for last night at Lola’s in Oak Bluffs.

Sunday afternoon’s public program at Union Chapel will be foreshadowed by the ringing of bells at Trinity United Methodist Church at 10 minutes of four. At that time, the Cottagers plan to walk in procession from Cottagers Corner to Union Chapel.

The program will include talked by Paula Giddings and Dr. James P. Comer.

Ms. Giddings, professor of Afro-American Studies at Smith College in Northampton, is the author of When and Where I Enter: The Impact of Black Women on Race and Sex in America. Harper/Collins plans to publish her forthcoming biography of anti-lynching advocate Ida B. Wells.

Dr. Comer is the Maurice Falk professor of child psychiatry at the Yale University School of Medicine Child Study Center. The founder of the Comer School Development Program in 1968, he has worked to promote community and teamwork within schools as a way of improving educational results.

Musical performances are scheduled from opera singer Lia Kahler, whose selections will include George Gershwin’s Summertime; the NAACP Spirituals Choir, a recently formed Vineyard group: the Constant Family Trio, a chamber music group from Brooklyn, N.Y., whose musical education has been supported by the Cottagers; and the Cottagers, the club’s own singing group, who will perform Old Cape Cod.

The Bob Moore Trio will provide jazz for the reception to follow.

During the program, the club is slated to receive printed recognitions from Gov. Mitt Romney, the Town of Oak Bluffs, and the NAACP state committee.

More is to come in the Cottagers’ summer. Next Thursday will bring an invitation-only gala at the Harbor View Hotel in Edgartown where, in the words of Ms. Allston, “the Cottagers get a chance to let our hair down and have a good time.”

At 5:30 p.m. August 11, an intergenerational discussion on where the Cottagers should go from here is scheduled at Cottagers Corner. The event is open to the public.

Aug. 15 will bring a clambake on Barnes Road in Oak Bluffs. The public is invited, although the event is selling out quickly. Admission is $50. Those planning to attend should call 608-693-8969 by August 9.

The Cottagers will bid adieu to summer during an open house form 5 to 7 p.m. August 34 at Cottagers Corner. The event is a way for the Cottagers to thank the Island for its support.

But the high point undoubtedly will be Sunday’s public program at Union Chapel, with its mix of speeches, music and presentations.

“Most of us started planning for this in August of 2005,” Ms. Baker said, “so we’re just most anxious to bring this to the public, and then just have that long, relaxing martini on the porch.”