Neutrino detectors for future experiments

We review detector technologies which are currently considered for ultimate nucleon decay searches, new generation astrophysical neutrinos studies, and for future long-baseline neutrino experiments at new high-intensity neutrino beam facilities. We focus our discussion on Phase-II experiments with a timescale of $10\simeq 20$ years. We point out that there are very few detector technologies which are general purpose and versatile enough in order to potentially address non-accelerator based physics and a large variety of future neutrino beam types ranging from superbeams, betabeams and neutrino factories from subGeV to 10's GeV energies.