One essential element of the European LTER process is a series of projects that help formalise and build the emerging eLTER Research Infrastructure. Currently, there are three active eLTER projects: PPP, PLUS, and EnRich:

Proof testing and innovating: eLTER PLUS is a HORIZON 2020 Advanced Community project and will identify and assess innovative observational and analytical methods, elaborate detailed specifications of eLTER RI according to community needs (standard observations, site design), support community building and training, and pilot priority services (IT and other support). 

Formalising: eLTER PPP (Preparatory Phase Project) is a HORIZON 2020 funded Coordination and Support Action for the detailed specification and high level decision making towards the level of legal, financial and technical maturity required for eLTER RI´s implementation.

Bridging to the eLTER RI: The Horizon Europe project eLTER EnRich will seamlessly link eLTER projects to eLTER ERIC operations by implementing a baseline ‘skeleton RI’ as a starting point for extensions during the RI operational phase, establishing essential cyberinfrastructure components and extending service capabilities, and building a solid and sustainable base of service hosts, future ERIC members, and engaged RI users.

A series of European funded projects preceded the current ones. Their focus ranged from networking and contributing to basic concepts for site categories, LTSER, and data integration including the SERONTO ontology (Alternet 2004-2009), to basic data architectures and integration mechanisms, controlled vocabularies, metadata for sites/datasets, and clarified RI-RI interactions  (EnvEurope 2010-2013 and ExpER 2010-2015).

In 2015 an eLTER ESFRI RM proposal led to ‘Emerging RI’ status, followed by a first community collaboration between the LTER-Europe network and the European Critical Zone Observatories that provides exemplary analyses to improve RI services (eLTER H2020 2015-2019).|

Last but not least, specific tasks for developing an operational RI were defined and an eLTER RI roadmap proposal was prepared and submitted (Advance_eLTER 2017).