On 16 July 2016, WG 179 sent a questionnaire to all PIANC National Sections to collect information about the applied classification for inland waterways in their countries and their suggestions for modernising the current ECMT (1992) and UN/ECE classifications. Based on the results of the questionnaire, the WG concluded that in Europe the connected waterways share a common classification. However, inland navigation and the inland waterways fleet in other countries is rather different from that in Europe. The WG started an investigation into developments in the inland waterways fleet in Europe and in particular into developments in waterway channel dimensions since the publication of previous classifications based on the proposal presented by PIANC WG 9 (1990). The overall waterway network was studied, and the specific dimensions of existing locks and bridges have been considered in drafting a new classification proposal. The structure of this report can be summarised as follows: The report is preceded with an executive summary. Here the new proposal for classification is introduced and the differences between the ECMT and UNECE classifications are highlighted and explained. The main conclusions and recommendations are listed in this summary. Chapter 1 contains the general introduction to the report. Chapters 2 and 3 deal with the programme of work and the results of the submitted questionnaires. Chapter 4 contains a description of fleet characteristics. Chapter 5 contains a description of waterway characteristics. Chapter 6 enhances the fleet and waterway characteristics findings through a market analysis. Chapter 7 presents the synthesis of the information presented in the previous chapters to develop the proposal for a revised classification, which is presented in chapter 8. Additional data and details are included in Appendices A to N.