For those working and interested in the field of chloroplast ribosomes, an ideal overview is provided by this text. Topics covered include: Plastid rRNAs and tRNAs; Structure, Organization and Expression of Their Genes; Plastid Ribosomal Proteins and Their Genes in Higher Plants; Plastid Ribosomes and Factors of Algae and of Cyanelles; Functional Aspects; Physiological Aspects. Stressed is the fact that biosynthesis and function of the translational apparatus relies upon two separate genetic systems and thus produce particular regulatory problems with fundamental significance. The evolutionary kinship of chloroplast and prokaryotic ribosomes is described as are some differences between them.