The field of quadrupole mass spectrometry has grown enormously since the early 1980's. The invention of the triple quadrupole mass spectrometer led to the development of tandem quadrupole mass spectrometers of many different configurations. A large number of tandem quadrupole mass spectrometers have also been developed by linking one or more quadrupole mass filters to a traditional magnetic or electric filter. The versatility of multiple quadrupole mass spectrometers along with their potential to rapidly produce a huge amount of data on a particular ion makes them ideal instruments for routine analytical analysis as well as for fundamental research The quinquaquadrupole mass spectrometer has been developed as an extension to the available multiple quadrupole systems. It offers the possibility to obtain even more data on the fragmentation of ions as well as enabling the study of novel ions to be carried out. The development of the quinquaquadrupole mass spectrometer forms the main part of this thesis. Also discussed are the reactions studied to evaluate the instrumental performance. The the ion molecule reactions of some halogen containing cations with saturated and unsaturated hydrocarbons performed on the triple quadrupole mass spectrometer are also discussed.