The publication series of Communications in Asteroseismology (CoAst) is one of the most important international journals in the field of asteroseismology. Asteroseismology is the science concerned with stellar pulsation. Every six months, CoAst publishes a newsletter with papers about the latest results and ongoing research projects. Besides these regular issues, special issues such as conference proceedings or software manuals are published in this series. CoAst Vol. 154 is a collection of the conference proceedings of the Delaware Asteroseismic Research Center and Whole Earth Telescope Workshop held in Delaware/USA in 2007. The proceedings provide the discussion of the latest theoretical as well as observational results mainly on white dwarfs.