This chapter considers phenomena of turbulent mixing that are specific and special to lakes. Most stratified turbulence processes, as depicted in Fig. 42.1 for lakes, occur both in the oceans and in lakes, and most of them are described in detail elsewhere within this book. The similarities to oceanic methods, observations, and theories are manifold. Comprehensive overviews of the hydrodynamics of lakes in a more general sense arc given, for instance, by Mortimer (1974), Hutter ( 1983), lmberger and Patterson (1990), Imboden and Wüest (1995), and Imberger (1998). Therefore, we will focus (a) specifically on turbulence and (b) on phenomena that are (i) either more important or (ii) more easily observed in lakes.