IALA G1128 is a guideline that provides information on how to develop specifications of e-Navigation Technical Services. In the past years, efforts have been made to use the guideline and its templates to successfully develop service specifications for maritime services, especially in the context of the Maritime Connectivity Platform. However, while applying the principles and templates as well as the supplied xsd-Schemas some smaller problems, or open points in the guideline could be identified. This TG aims to proprose a revised version of the guideline.