Evaluations of potential effects on honey bee brood are an important part of the registration process of PPPs. The recently used methodology to investigate bee brood development under realistic exposure conditions are semi-field studies according to Schur et al. (2003) (see section 5.2.2. in this manuscript) superseded by the OECD Guidance Document No. 75 or field studies according to Oomen et al. (1992) (see section 5.2.1. in this manuscript). Originally, at least 100 brood cells have to be marked and evaluated on acetate sheets with overhead markers for both methods. This is time consuming. The disadvantages of the “acetate method” are the restricted number of cells that can be marked and the long “off-hive-time” of the brood combs. Therefore a digital image processing method was developed (Wang & Claßen, 2011, Jeker et al., 2012;) to reduce the “off-hive-time” of the single brood combs and therefore the stress for the whole honey bee colony. In principle, the use of digital image processing allows one to evaluate the development of an unlimited number of brood cells resulting in increased statistical power. Further, the digital method allows one to re-evaluate the brood development of single cells in the case of uncertainties.