Expansions and transitions are coming to the West Marin Fund, the community foundation that has supported West Marin nonprofits since it was founded in 2010. Catherine Porter, the part-time executive director, has announced that she is resigning. Her replacement will work fulltime, allowing the fund to step up its donor base, grants and programs. 

To appeal to more donors, the fund has also adopted a new mechanism for philanthropists: a donor-advised fund. Harriet Moss, the…