Abstract: A back support device is disclosed comprising a belt structure designed to fit substantially around the waist of a user. An inflatable air bladder is attached inside the belt structure so that it is positioned adjacent to the lower back when the back support device is worn. Several embodiments of elastic strap members are disclosed which are attached between the air bladder and belt structure. The strap members enable the user to adjust the direction of force exerted by the air bladder on the lower back and helps to pull the air bladder around the waist. A manual air plump with two-way valve is positioned inside the belt structure near one end which enables the user to selectively adjust the amount of air in the air bladder while the back support device is worn. Using the above device, a method of providing back support is also disclosed.