Reliable assembly methods are needed to translate new endoscopic probes from the research phase to clinical testing. Design variation complicates standardized assembly and leads to a lengthy process creating inaccurate prototypes, preventing repeatable research. This thesis proposes a strategy for selecting the most effective assembly method by examining alignment and bonding relations among parts. Considering the manufacturing tolerances of the optical parts leading to a loss of image quality, an approach for testing is selected to align the gradient index (GRIN) lens and fibre. This approach implements an active alignment procedure and reaches a sensitivity of 3𝜇𝑚 for the concentricity, 0.4 deg for the colinearity and 40𝜇𝑚 for the separation distance. These results validate a better result than reachable with passive alignment. An optimization algorithm could replace the manual comparison of the ideal beam profile for increased repeatability. To advance the research to the assembly of complete prototypes, more components of the probes should be added to the investigation and a method for fixing the components to the housing should be introduced.