The work of this thesis focuses on two aspects of a 12U CubeSat mission: mission analysis and trajectory design and optimization. The project in question is Space Rider Observe Cube (SROC), an innovative ESA demonstration mission carried out by a CubeSat that will be deployed from Space Rider; the mission aims at demonstrating critical capabilities and technologies required to successfully execute a rendezvous and docking mission in a safety-sensitive context. Moreover, the project aims at demonstrating key technologies in the area of proximity operations, especially in the domain of in-orbit servicing, space exploration, and debris mitigation. The trajectory design and optimization are achieved by the update and the enhancement of a Matlab code, previously created by Politecnico di Torino, which interfaces the user with an STK scenario through the STK Object model software interface.