As was seen in Part I, the treatment of the reaction of a nonporous solid particle is relatively straightforward. When the solid is initially porous, analysis becomes rather involved due to the fact that chemical reaction and diffusion occur in parallel. Only recently, some noteworthy developments and articles have been reported as the importance of this type of systems is being recognized more and more. In this Part II, recent advances on the reaction of a porous solid particle will be discussed. In the next two parts, we will describe the reactions between two solids proceeding through gaseous intermediates and the treatment of industrially important multiparticle systems.