Before discussing teaching, it seems appropriate to acknowledge[11] that there was a time not long ago when teaching skills were of little importance[29] to many institutions[30] . (See for example[12] the discussion of the Princeton math department in the 1950s in Sylvia Nasar’s A Beautiful Mind.) Several factors are contributing to a change in this regard. The United States is a nation at risk in terms of precollegiate mathematics education, but if we do not succeed in teaching mathematics to the undergraduate students we get, even if these students are not all highly[31] motivated and not all well prepared, then our nation will not be able to maintain the scientific work force it needs. At the same time, college tuition is large and growing, and consumers rightly[32] expect that the product they purchase will be worth the cost. And it is not a given that as math faculty retire[13], they will be replaced[14] by new faculty. If we cannot succeed at the teaching of mathematics to undergraduates, then the pressure to have others do so in our place will increase. In the long run, then, mathematics will do better if the next generation[33] of mathematicians on university faculties are excellent teachers. The topic of this article should thus be of genuine importance to the entire[15] math community.