  This is a survey on the recent progress in several applications of
isoparametric theory, including an affirmative answer to Yau's conjecture on
the first eigenvalue of Laplacian in the isoparametric case, a negative answer
to Yau's 76th problem in his Problem Section, new examples of Willmore
submanifolds in spheres, a series of examples to Besse's problem on the
generalization of Einstein condition, isoparametric functions on exotic
spheres, counterexamples to two conjectures of Leung, as well as surgery theory
on isoparametric foliation.
