This official NASA internal document - converted for accurate flowing-text ebook format reproduction - contains extraordinary commentary from astronauts associated with the Skylab program on a variety of operational issues and spacecraft systems, with fascinating opinions on medical issues, EVA umbilicals, spacecraft recovery options, communications, and much more. From the introduction:Skylab has more to offer than the results of its scientific efforts. The operations that were conducted by the Skylab crews and ground personnel represent a rich legacy of operational experience. As we plan for our return to the moon and the subsequent human exploration of Mars, it is essential to use the experiences and insights of those who were involved in previous programs. Skylab and Skylab Medical Experiments Altitude Test (SMEAT) personnel possess unique insight into operations that are being planned for the Constellation Program, such as umbilical extravehicular activity (EVA) and water landing/recovery of long-duration crew members. The Skylab Program was also well known for its habitability and extensive medical suite; topics that deserve further reflection as we prepare for lunar habitation and missions beyond Earth's sphere of influence.The Skylab Medical Operations Summit was held in January 2008. Crew members and medical personnel from the Skylab missions and SMEAT were invited to participate in a 2-day summit with representatives from the Constellation Program medical operations community. The purpose of the summit was to discuss issues that will be pertinent to future Constellation operations.The purpose of this document is to formally present the recommendations of the Skylab and SMEAT participants. As we look to the future of space exploration - our return to the moon and quest for Mars - we must remain mindful of those who opened the heavens to the long-duration exploration of space. The International Space Station (ISS) and Constellation Programs are the stewards of the Skylab legacy. The hard-won lessons of Skylab can still guide us as we extend mankind's presence in space.