European Spallation Source, ESS, is an upcoming accelerator-based neutron source that will be built in Lund, Sweden. The facility will become operational in 2019 and will offer a variety of instruments for material sciences, biology, chemistry, fundamental physics and engineering studies. In this presentation I will introduce the field of neutron scattering and give examples of instrument concepts currently in operation and those to be built at the ESS. A particular challenge currently faced by all applications that use thermal neutron detectors is the dramatic rise in price of He3 that has occurred in the past few years. This prompted several parallel research and development efforts aimed at replacing He3 with other converter materials. I will focus on the development of detectors based on B10 layers in ESS which is primarily aimed at the Instruments where 10s of square meters of detector coverage are required, and which are, therefore, most severely affected by the He3 shortage.