I completely agree with Local here. A former teacher of mine who was in many orchestra's on the east coast and was a former student of Armando Ghitalla and William Vacchianno had some serious air leakage on each side of the mouth - and, indeed, sounded FANTASTIC. Could he have been more efficient without this air leakage? Maybe. But he, irregardless of this "problem", sounded amazing. My advice to 7cjbill2 would be to get a GREAT concept of sound by listening to recordings, watching others play, etc. (It takes years to develop this!) Your brain and body, so long as you put the neccesary hours into the practice room, will unconciously make steps towards a more efficient system. In the process, symptoms like leaking air around the embouchure will likely be "forgotten". Also, a lot of great concepts and philosophies on brass playing espoused here are taken right from Arnold Jacob's Song and Wind, which you might want to take a look at. Like Local says, this superficial leaking air around the embouchure "problem" is most likely a symptom of bigger fundamental problems - but at the same time could just be a natural facet of your playing.