The White Dwarf Companions of Recycled Pulsars
  I review what properties of the white-dwarf companions of recycled pulsars can be inferred from optical observations, and discuss how these can help us understand the characteristics and evolution of these binaries. I focus on spectroscopic observations, describing results obtained recently, and looking forward to what may come. 
M. H. van Kerkwijk (Palomar Observatory, Caltech)