Recently a great deal of theoretical and experimental interest has been directed at a class of magnetic materials which undergo phase transitions at zero temperature. These ‘quantum phase transitions’ are driven by quantum (or zero-point) fluctuations, which are reflected in exotic magnetic behaviour near the boundaries between phases. We have recently reported a study on a compound Cu(pyz)(gly)(ClO4), which comprises a network of spin-dimers and exhibits two phase transitions as a function of magnetic field. The experimental accessibility of both of these magnetic field driven transitions permits a unique opportunity to study the magnetic excitations in each of the low temperature phases. We shall therefore directly investigate the role of the quantum fluctuations in the vicinity of the crossovers, where they are predicted to influence the nature of the excitations.