Kristen do research on host-pathogen interactions, specifically on bacteria which infect arthropods, such as insects. Some bacteria are beneficial to their hosts, fx. by supplying nutrients, others are parasitic and may eventually kill their hosts. The goal of her research is to find clues as to how the bacteria live with and adjust to their hosts, and she do so by looking at the genetic material of the bacteria. Kristen daily work includes both laboratory work, i.e. cloning, sequencing and maintenance of infected fruit-fly stocks, and various data analysis.