WASHINGTON  The State Department will offer equal benefits and protections to same-sex partners of American diplomats, according to an internal memorandum Secretary of State Hillary Rodham Clinton sent last week to an association of gay and lesbian Foreign Service officers.

Mrs. Clinton said the policy change addressed an inequity in the treatment of domestic partners and would help the State Department recruit diplomats, since many international employers already offered such benefits.

“Like all families, our Foreign Service families come in different configurations; all are part of the common fabric of our post communities abroad,” Mrs. Clinton said in the memorandum, a copy of which was provided to The New York Times by a member of the gay and lesbian association.

“At bottom,” she said, “the department will provide these benefits for both opposite-sex and same-sex partners because it is the right thing to do.”