A piece of furniture having an adjustable platform comprising: a main frame having a support platform mounted thereon; a fixed frame base having wheels mounted thereto for displacement of the base on a floor surface, the base remaining stationary when the main frame is displaced relative thereto by a lift mechanism interconnecting the main frame and the base; and wherein the lift mechanism supports the main frame and is actuable to displace and position the main frame at any point between a fully collapsed position, wherein the support platform is located at a minimum vertical height above the floor surface, and a fully extended position, wherein the support platform is located at a maximum vertical height above the floor surface; wherein the lift mechanism comprises: two or more leg members each having a first end pivotally connected with the fixed frame base at a lower pivot and a second end pivotally connected with the main frame at a movable upper pivot; at least one stabilizer link for each said leg member, the stabilizer link having an upper end pivotally connected with the main frame and a lower end pivotally connected with each said leg member at an intermediate pivot point disposed on the leg member between the first and second ends thereof; and an actuating assembly including at least one actuator for each said leg member, the actuator having a first end engaged to the main frame and a second end pivotally connected with a force multiplying actuating linkage pivotally interconnecting the actuator and the stabilizer link. a main frame having a support platform mounted thereon; a fixed frame base having wheels mounted thereto for displacement of the base on a floor surface, the base remaining stationary when the main frame is displaced relative thereto by a lift mechanism interconnecting the main frame and the base; and wherein the lift mechanism supports the main frame and is actuable to displace and position the main frame at any point between a fully collapsed position, wherein the support platform is located at a minimum vertical height above the floor surface, and a fully extended position, wherein the support platform is located at a maximum vertical height above the floor surface; wherein the lift mechanism comprises: two or more leg members each having a first end pivotally connected with the fixed frame base at a lower pivot and a second end pivotally connected with the main frame at a movable upper pivot; at least one stabilizer link for each said leg member, the stabilizer link having an upper end pivotally connected with the main frame and a lower end pivotally connected with each said leg member at an intermediate pivot point disposed on the leg member between the first and second ends thereof; and an actuating assembly including at least one actuator for each said leg member, the actuator having a first end engaged to the main frame and a second end pivotally connected with a force multiplying actuating linkage pivotally interconnecting the actuator and the stabilizer link. two or more leg members each having a first end pivotally connected with the fixed frame base at a lower pivot and a second end pivotally connected with the main frame at a movable upper pivot; at least one stabilizer link for each said leg member, the stabilizer link having an upper end pivotally connected with the main frame and a lower end pivotally connected with each said leg member at an intermediate pivot point disposed on the leg member between the first and second ends thereof; and an actuating assembly including at least one actuator for each said leg member, the actuator having a first end engaged to the main frame and a second end pivotally connected with a force multiplying actuating linkage pivotally interconnecting the actuator and the stabilizer link.