Invited Articles -- Progress in Quantum Algorithms -- NMR Quantum Information Processing -- Quantum Computing with Trapped Ion Hyperfine Qubits -- Ion Trap Quantum Computing with Ca+ Ions -- Quantum Information Processing in Cavity-QED -- Quantum Information Processing with Trapped Neutral Atoms -- The Road to a Silicon Quantum Computer -- Controlling Spin Qubits in Quantum Dots -- Spin-based Quantum Dot Quantum Computing in Silicon -- Optically Driven Quantum Computing Devices Based on Semiconductor Quantum Dots -- Implementing Qubits with Superconducting Integrated Circuits -- Towards Scalable Linear-Optical Quantum Computers -- Photonic Technologies for Quantum Information Processing -- Contributed Articles -- Quantum Computer Development with Single Ion Implantation -- Bang-Bang Refocusing of a Qubit Exposed to Telegraph Noise -- Quantum Computing and Information Extraction for Dynamical Quantum Systems -- One-Dimensional Continuous-Time Quantum Walks.Practical quantum computing still seems more than a decade away, and researchers have not even identified what the best physical implementation of a quantum bit will be. There is a real need in the scientific literature for a dialog on the topic of lessons learned and looming roadblocks. These papers, which appeared in the journal of "Quantum Information Processing" are dedicated to the experimental aspects of quantum computing These papers highlight the lessons learned over the last ten years, outline the challenges over the next ten years, and discuss the most promising physical implementations of quantum computing.