Abstract: An undergarment and undergarment changing accessory system includes an undergarment, at least one changing accessory for cleaning or treating an undergarment wearer or caregiver, and a container comprising sheet portions that are partially sealed together with releasable seals along perimeter edge portions that may be readily pulled or peeled apart to expose the undergarment (such as a diaper) and changing accessory contained therein. A fixed or non-releasable seal or fold region may optionally connect the sheet portions after the releasable seals are opened so that the sheet portions form an enlarged sheet that can be used as a sanitary changing surface. A releasable seal established along a divider portion between the sheet portions and separating the undergarment from the changing accessory maintains the undergarment and changing accessory in isolation from one another and from the environment to prevent leaks or contamination prior to opening the releasable seals.