Dr Kristina Thomsen is a senior physicist in the Luminescence Research Laboratory (LRL), at The Centre for Nuclear Technologies, DTU Risø Campus, Denmark. The LRL has more than 30 years of experience in luminescence research, including retrospective luminescence dosimetry (e.g.  archaeological and geological dating and personal dosimetry) and in the development and manufacture of instrumentation. In particular, the LRL produces the Risø TL/OSL reader, of which more than 350 are used by luminescence research and dating laboratories around the world; over the last 15 years >85% of all published luminescence dating has a been undertaken on the Risø instrumentation. Kristina Thomsen has been heavily involved in the research and development of this technology throughout this period, particularly concerning new radiation and optical stimulation sources and instrumentation for single grain measurement. Her fundamental and applied research interests lie in the field of retrospective radiation dosimetry with a main focus on optically stimulated luminescence (OSL) from natural dosimeters and its application to environmental and accident dosimetry. She has been particularly involved in investigations of the origins of dose distributions measured using individual grains of sediment and in understanding charge transport mechanisms in natural dosimeters (feldspar) with the aim of identifying stable luminescence signals. Her work has led directly to the development of a new model for the luminescence production in feldspar and to the increasingly widespread use of feldspar as an accurate retrospective dosimeter at high doses. This has resulted in an extension of the datable age range by luminescence techniques by approximately a factor of 5.