The organization was initially known as the Catholic Welfare Bureau, an integral part of the Federation of Catholic Charities that established social services, an orphanage, home for the aged, and two hospitals. They also organized the Community Chest, which was a forerunner of the United Way.

The work of the early organization was primarily providing financial assistance to the poor. As well Father Cook and three other volunteers offered counselling to families impacted by the disruption and dislocation of WW II. The Catholic Welfare Bureau continued to provide basic welfare services but also added counselling and intervention to deal with the increased number of fractured marriages as a result of the war.

In 1955 the name of the organization was changed to the Catholic Family Centre to support the growing need for family and marriage counselling. And while welfare services were eventually taken over by the government, the Catholic Family Centre remained a charter member of the United Appeal, now known as the United Way. The agency was incorporated in 1973 and became an independent entity that provided service for healthy family relationships, community planning, youth diagnostic and referrals services, adult education to prevent marriage and family breakdown, professional social work and social welfare education, research, and emergency assistance to families.

In 1975 the name was changed to the Family Counselling Centre recognizing the transition from an agency serving the Catholic poor to one serving the whole community. In 1985 the name was changed again to Family Service London to reflect the relationship with the national association of Family Service Canada, and later changed to its current name. Consistent themes throughout the history of the organization include providing accessible service to anyone in need, being adaptable and flexible to the needs of the community, and providing highly skilled counselling services to individuals, couples and families.