  Sauter-Schwinger pair creation in electromagnetic fields is a fundamental
prediction of QED and one of the motivations for the present efforts in
constructing super-strong lasers. I will give a historical review of the
subject, and then focus on two recent developments. The first one is the
worldline instanton formalism, a sophisticated version of the WKB approximation
that makes it possible to calculate the pair creation rate for complicated
field configurations. The second one is an adaptation of the
Dirac-Heisenberg-Wigner formalism suitable for a detailed study of the
formation of real particles in time and space.
