Various aspects of the dissociation dynamics of multiply charged molecular ions have been studied by use of time-of-flight mass spectrometry, a photoion-photoion (PIPICO) coincidence technique, and a photoelectron-photoion-photoion coincidence method together with a source of synchrotron radiation The ion branching ratios for the individual ions respectively produced from the precursors  CO⁺, CO²⁺ , and CO³⁺ have been determined separately at the excitation energies where the molecular and dissociative single-, double- and triple-photoionization processes compete. Kinetic-energy release in the dissociation of NO²⁺ and the angular distributions of the fragment ions produced from OCS²⁺ have been obtained by analyzing the PIPICO spectra. The dissociation mechanisms of OCS²⁺ into three bodies are presented. In addition, site-specific fragmentation of the organometallic molecule, 1,1,1-trimethyltrichlorodisilane, after Si:2p core-level excitation and ionization has been investigated.