An upholstered furniture system having removable and intechangeable spring and sleeper units (32, 34) for mounting on a substantially horizontal surface. The system comprises first and second (22) spaced apart substantially vertical arm members, a back member (26) which is removably attached to the arm members and a front member (20) which is in removable contact with the arm members. A seat support member, which may be one of a spring platform (32) and a sleeper mechanism (34), is removably supported by first and second side support sections (56) affixed to the inner surfaces of the first and second arm members (22). A cover (94) may be secured to the arm, back and front members by hook and loop fastening strips (96).