A portable, inflatable support system, and a portable inflator for use with such a system are provided in one embodiment. The inflatable support system may include an inflatable mattress having a pressure valve and a battery powered inflator for removable engagement therewith, which on engagement is automatically powered for a predetermined time or until a predetermined pressure is achieved. The mattress may be readily expanded for use and collapsed for storage. Another embodiment provides a multipurpose pressure control, for manual adjustment to provide an inflatable support system of desired firmness, and to modify the posture of the reclining user. A dual valve assembly includes a cover assembly that removably covers a throat, and the cover assembly is itself provided with a one-way valve. Another embodiment provides an in-place bedding system, including a mattress, mattress cover, and top and bottom bedsheets, which retain their functional arrangement when the bed is collapsed for storage and prepared for use, thereby eliminating the necessity for re-making the bed with each use.