Answer
Molecular self-assembly is the primary technique employed by Stoddart in his research. This technique involves the spontaneous organization of molecules into complex and well-defined structures without external intervention. Stoddart's research focuses on creating molecules that can self-assemble into functional systems, such as molecular machines and sensors. By harnessing the power of self-assembly, Stoddart aims to develop new materials and technologies with applications in various fields, including medicine, energy, and computing.