  Achieving control over the electron spin in quantum dots (artificial atoms)
or real atoms promises access to new technologies in conventional and in
quantum information processing. Here we review our proposal for quantum
computing with spins of electrons confined to quantum dots. We discuss the
basic requirements for implementing spin-qubits, and describe a complete set of
quantum gates for single- and two-qubit operations. We show how a quantum dot
attached to leads can be used for spin filtering and spin read-out, and as a
spin-memory device. Finally, we focus on the experimental characterization of
the quantum dot systems, and discuss transport properties of a double-dot and
show how Kondo correlations can be used to measure the Heisenberg exchange
interaction between the spins of two dots.
