SpaDeX or Space Docking Experiment is a twin satellite mission developed by the Indian Space Research Organisation (ISRO) to mature and demonstrate technologies related to orbital rendezvous, docking, formation flying, which will have future applications in areas such as human spaceflight, in-space satellite servicing and other proximity operations.

[10] According to ISRO, the SpaDeX mission had the following objectives: The research and development (R&D) needed to complete the project began with preliminary studies in 2016.

[22] As per the previous head of ISRO, S. Somanath, docking is a crucial component for Chandrayaan-4 and that SpaDeX is intended as a demonstrator and forerunner.

As per Mylswamy Annadurai, the project director of the Chandrayaan-1, the demonstated docking technique will aid in the future management of space debris.

[27][28][29] The Italian company Leaf Space, which offers ground segment-as-a-service (GSaaS) solutions, partnered with ISRO to create communication linkages with the POEM-4 platform and the SpaDeX satellites.

[30] The designations SDX01 and SDX02 are assigned to the "Chaser" and "Target" satellites, respectively, though both host docking devices capable of active or passive function.

[32] The Space Applications Centre developed a miniaturized high-resolution camera with photo and video capability that was carried aboard SDX01.

During docking operations, an Inter-Satellite Communication Link (ISL) provided smooth data transmission, improving the system's dependability and autonomy.

With 60–70% propellant remaining and the project expense being fully utilized, more docking, undocking, and power transfer experiments will be conducted.