This volume is comprised of a series of papers dealing with some of the current unsolved problems in the field of stellar physics. It is also a celebration of the contributions made to this subject by Prof. Douglas Gough. Topics discussed include: stars, interiors, stars: evolution, asteroseismology, helioseismology, and fluid dynamics. The book will appeal to researchers in the fields of helioseismology, asteroseismology, stellar evolution, stellar physics and fluid dynamics.