This opinion provides the relevant data, evaluations and references that support the criteria proposed in the new draft guidance needed to facilitate assessment of dermal absorption of plant protection products (PPPs) under Directive 91/414/EEC4 and Regulation (EC) No 1107/20095. The new guidance will be finalised and published only after adoption and publication of this opinion. This opinion has been developed after a public consultation of EFSA on the current guidance document and an outsourced project carried out by the UK Chemicals Regulation Directorate (CRD, 2010). It is not intended to be an exhaustive review but builds on existing documents to which the reader is referred to, and addresses in more detail elements that are specifically relevant for the assessment of dermal absorption of plant protection products. It contains an overview on skin and substance properties and other determinants that have an impact on absorption, a description of important elements in the design of experimental studies and an analysis of available data on dermal absorption of PPPs. The PPR Panel concludes that assessment of dermal absorption in the absence of specific studies can be performed based on default values that the Panel derived from the analysis of the available databases. Elements for a tiered approach are described and commented on. The PPR Panel also concludes that in vitro human studies can be used as a stand alone test for assessment of dermal absorption. The Panel indicates some additional requirements to adapt existing OECD test guidelines to the special requirements of PPPs and their formulations. A harmonised reporting of the studies is also considered important. Some areas where further research could usefully be conducted have been identified.