  High field superconducting magnets using high temperature superconductors are
being developed for high energy physics, nuclear magnetic resonance and energy
storage applications. Although the conductor technology has progressed to the
point where such large magnets can be readily envisioned, quench protection
remains a key challenge. It is well-established that quench propagation in HTS
magnets is very slow and this brings new challenges that must be addressed. In
this paper, these challenges are discussed and potential solutions, driven by
new technologies such as optical fiber based sensors and thermally conducting
electrical insulators, are reviewed.
