There are many well-qualified scientists who question long-established physics theories even when paradigms are not in crisis. Challenging scientific orthodoxy is difficult because most scientists are educated and work within current paradigms and have little career incentive to examine unconventional ideas. Dissidence is a strategic site for learning about the dynamics of science. Dozens of well-qualified scientists who challenge dominant physics paradigms were contacted to determine how they try to overcome resistance to their ideas. Some such challengers obtain funding in the usual ways; others tap unconventional sources or use their own funds. For publishing, many challengers use alternative journals and attend conferences dedicated to alternative viewpoints; publishing on the web is of special importance. Only a few physics dissidents come under attack, probably because they have not achieved enough prominence to be seen as a threat. Physics could benefit from greater openness to challenges; one way to promote this is to expose students to unconventional views.