Proton therapy is a precise method to treat deep-seated tumours, using accelerator produced proton beams. However, for valid predictions of the proton range and dose deposition due to the depth-dose characteristics of the ion beam, it is necessary to know the stopping power inside the patient. One method to achieve this goal is Proton Computed Tomography (pCT), which measures the energy loss of protons at the plateau of the Bragg curve. The main advantage of pCT is that the same type of particles used for therapy is used to measure the stopping power distribution. A pCT setup basically consists of a tracker, which should be able to reconstruct the particle trajectory through the patient and a calorimeter to measure the deposited energy in the patient. The tracker should be able to achieve single particle counting, which requires low particle fluxes. Therefore three different particle flux reduction methods, provided by MedAustron had to be tested experimentally. For this purpose a VME based particle counting and trigger system (PCTS) was developed within this thesis. With this PCTS system, fluxes down to 1 104 p/s were measured. In order to calculate the stopping power in the patient correctly, the path of the traversing proton has to be estimated. For this purpose a tracking telescope, consisting of four double-sided silicon strip detectors was designed, simulated with Geant4, optimized and tested experimentally. The scattering power of a plastic phantom, mounted on an in-house made rotary table, was measured and compared to the Geant4 Monte Carlo simulation. The results showed that a functioning beam telescope, which is able to perform particle tracking could be installed. Also the experimentally obtained distorted beam profiles showed similarities to the simulated beam profiles. This tracker combined with a suitable calorimeter would form together a full pCT setup.