Abstract: Recent experimental and theoretical research on spin qubits in quantum dots have clearly demonstrated that spins have long coherence times and can be reliably controlled. Electron spin two-qubit gates can be performed using the strong exchange interaction between dots, which however is short-ranged. How to achieve long-range quantum communication for spin qubits remains a significant open problem in the scale-up of spin qubit architectures. Here I give an overview of the various approaches to achieve spin information transfer, such as those based on spin-photon coupling, or based on a spin bus made from a spin chain. I will then focus on a particular approach that involves the transportation of the electrons themselves, which is attractive because of its conceptual simplicity and its similarity to the conventional charge-coupled devices. I will discuss our recent work on the physics of electron spin decoherence when the quantum dot is in motion. Specifically, we find that the motion induced spin decoherence is a pure longitudinal relaxation channel, whose rate depends on the disorder in the substrate, the strength of the magnetic field, and the speed of the quantum dot motion. Our results not only show how severe a problem this decoherence could be, but also clearly indicate how to reduce the decoherence effects of electron motion.