Thomas Bindel and Dieter Hofmann highlight the similarities and differences between the standards DIN 19227 and DIN EN 62424 for the development of R&I flow diagrams/R&I flow charts. DIN 19227, Part 1 (Graphical Symbols and Designation Letters for Process Control Technology) has been withdrawn and replaced by DIN EN 62424 (Representation of Tasks in Process Control Technology - Flow Diagrams and Data Exchange between IT Tools for Flow Diagram Creation and CAE Systems), but it remained in effect until July 2012. Since flow diagrams for older systems were developed according to DIN 19227, users face the challenge of still needing to understand this standard, while for newly constructed systems, DIN EN 62424 must be applied, which seems to be adopted rather hesitantly. The authors illuminate the changes associated with the transition and provide guidance on the use of DIN EN 62424.