We are developing novel neutron detectors and spectrometers for applications in homeland security, radiation protection, and basic research. Development of sensitive neutron detectors is motivated primarily by needs for measurement services and standards for homeland security applications, such as personnel radiation dose measurements in the vicinity of active interrogation devices (used for inspection of packages and cargo) and the detection of contraband shipments. Another active area of investigation is the use of muon anti-coincidence or other methods to distinguish background neutron counts (such as from the showers of cosmic rays) from neutrons of interest. Such detectors also have applications in low-background and underground science.