eLML, the open source “eLesson Markup Language”, is an XML framework allowing authors of e-Learning lessons to create structured and sustainable content. eLML is based on the pedagogical concept ECLASS (adapted from Gerson, 2000), standing for entry, clarify, look, act, self-assessment and summary. Each lesson is divided into units that contain a number of smaller learning objects. To allow different teach- ing and learning scenarios most of the structure elements are optional or can be repeated several times and different orders. Lessons written with eLML can be transformed into HTML or PDF or be imported into a learning management system (LMS) using the SCORM or IMS Content Packaging format. The paper pre- sents experiences from the development of eLML itself, the design of e-Learning content based on the eLML-structure, and the use of eLML-based content in conjunction with a LMS.