Chloroplasts are photosynthetic organelles containing a part of plant genome usually called plastome. Introduction of foreign genes into plastids and creation of transplastomic plants has some advantages over classic nuclear transformation, so chloroplasts are of great importance for biotechnology. Chloroplast gene expression machinery is diverse and complicated. Apparently, it was inherited from a cyanobacterial ancestor but evolved greatly in eukaryotic plant cell. Transcription is the first stage of gene expression and the review focuses on plastid transcription apparatus. Higher plant chloroplasts have two RNA polymerases, one of bacterial origin (PEP) and the other arose from mitochondrial one (NEP). Only one (or two) general transcription factor (sigma) was inherited from cyanobacteria but in the evolutionary process it gave rise to a small gene family with at least partially non-redundant functions. It is likely that at least in dicotyledonous plants, multisubunit RNA polymerase received about ten extra polypeptides and is hardly inhibited by a well-known bacterial antibiotic – rifampicin. The review is illustrated with the examples of successful application of this knowledge in introduction and expression of foreign genes in chloroplasts (Lysenko 2010).