Ribonuclease P is among the first ribozymes discovered, and is the only ubiquitously occurring ribozyme besides the ribosome. The bacterial RNase P RNA is catalytically active without its protein subunit and has been studied for over two decades as a model system for RNA catalysis, structure and folding. This review focuses on the thermodynamic, kinetic and structural frameworks derived from the folding studies of bacterial RNase P RNA.