(1) Adaptation to lunar gravity is quick and easy; working in it is FUN!

(2) The radiation environment is going to be a major restraint to long-duration operations on the lunar surface.  Shielded habitats will be essential if crews are to spread permitted exposure to the cosmic ray background over stays of significant lengths.  Provision of emergency sheltering against infrequent but dangerous solar particle events will be essential for forays away from permanent facilities.

(3) Dust is a major operational hazard.  Provision must be made for doing more thorough cleaning of gear before it is brought inside than was possible during Apollo.  Jack Schmitt (Apollo 17) has been talking about the need for "dust locks" for a long time and something along those lines may be essential.

(4) Limited manual dexterity, forearm fatigue, and damage to fingers and fingernails were all issues arising from the Apollo gloves.

(5)  There was little opportunity - or need - to do equipment maintenance or repair during Apollo.  Trade-offs between the 'cost' of replacement of limited life-time gear - such as various suit components - and the 'cost' of a maintenance/repair capability must be assessed.

(6) Despite 1/6th gravity, carrying the ALSEP packages was hard work.  A transporter of some sort for bulky and/or heavy items will be essential.

(7)  Judging size and distance on the airless moon can be challenging but probably can be overcome through experience, perhaps aided by simple laser-ranging devices.

(8)  Navigation is not difficult,  given knowledge of the solar elevation and azimuth, simple devices like a sun compass, decent maps, and horizon features.  With a bit better preparation, the Apollo 14 crew probably would have found the rim of Cone Crater.  Photogrammetric analysis of the Apollo 11 site suggest that, for long-range traverses away from a base, crews could located themselves accurately using a small navigation device combining digital imagery from on-board cameras with a data base of boulder locations derived from orbital imagery, eliminating the need for - and cost of - GPS-type systems.

(9) The main product of any mission of discovery is a shared sense of awe and pride.  Thinking back over our first fifty years in space, the vehicle of that shared experience is imagery.  It took a while for NASA to learn that lesson.  The Hasselblad images are priceless and there should be more.  The television from A11 was embarrassing, especially given that better color cameras were available.  A12 and A14 weren't much better and even A15 suffered because Houston didn't request that the crew dust the lens often enough.  We've learned a lot since then. Apollo 16 and 17 TV imagery was by far the best from Apollo, largely due to real-time processing of the received signals by John Lowy, founder of Lowrey Digital.  Imagery from the Shuttle missions, from ISS, and from the Mars Rovers are the products of great advances in camera technology since Apollo.  Future missions should have imagery at the very top of the priority list.  From Phil Karn (US):  "Pictures are what pay NASA's bills  ... High resolution digital cameras have become small, light, and excellent.  Orion and Altair should bristle with them."  Where data bandwidth is an issue, intelligent management of framing rate, resolution, and duty cycles will be of great value. For example, software could be used to transmit imagery only from cameras seeing non-static scenes.

(10) Ron Wells (US) wrote, "Train, train, train.  Train in the most real conditions capable of  being simulated, not only for the flight crews but also the flight director teams, separately and together."  As Dave Scott has repeatedly emphasized, make sure that management gets a good understanding of the work that will be done by having them observe training.

(11) From Harald Kucharek (Germany):  "Always have a hammer and duct tape close at hand"; they are great problem solvers. Examples are (a) A12 RTG fuel element extraction; (b) adapting A13 CM LiOH canisters for use with the LM ECS; (c) securing cables on the A15 Rover; (d) making the A17 replacement fender; (e) and almost certainly others.

(12) From Phill Parker (UK): "Think big and be positive."

(13) From Phil Karn (US): "Cutting corners doesn't pay in the long run. Not just  the obvious stuff like the rush that led to the Apollo 1 disaster, but  also the many design compromises that sacrificed endurance in order to  get us to the moon more quickly and/or cheaply ... Getting humans and hardware to the lunar surface is a very expensive and  dangerous undertaking, and it was a shame they had to turn around and  come back almost as soon as they arrived."

(14)  Lunar surface activities conducted during Apollo fell into two broad categories: (1) exploration and (2) the operational/procedural context that made exploration possible.  Exploration is overwhelmingly investigative and requires that crew members acquire, through training, the ability to recognize and evaluate key features of landforms and samples and use those in deciding how to best use time available.  Operational training requires a familiarity with procedures and equipment to the extent that the work can be done efficiently, and that problems can be handled on site or discussed knowledgably with support personnel. Some of the moonwalkers were well-prepared for both.  Among the early crews, Armstrong was a standout.  All six of the J mission crewmen were, too.  Professional geologist Jack Schmitt became a very credible LMP; and, in the same vein, professional pilots Scott, Irwin, Young, Duke, and Cernan became credible field geologists with a good understanding of the questions and of the methodology for making appropriate observations and collecting relevant samples.

(15) In exploration phases of the mission, more than in operational phases, management/flight directors should expect and encourage real-time crew decisions.  STS and ISS are more operationally focused than were Apollo lunar surface activities.