A interesting new possibility of detection of ultra-high energy (UHE) neutrinos is that of acoustic detection whereby the acoustic pressure pulse generated as a UHE neutrino interacts in a suitable medium such as water or ice is detected by an array of acoustic sensors. Recent years have seen something of a renaissance of this field and there are currently a number of activities worldwide to assess the potential of this technique. The UK-based ACORNE collaboration is one of these activities. The talk will present an introduction to neutrino astrophysics, explain the acoustic detection technique and summarise ACORNE’s R&D work, including simulation, potential neutrino flux sensitivities, calibration and data acquisition at an existing hydrophone array in Scotland.