Only researchers located in the following HERA JRP countries are eligible to apply, irrespective of their nationality: Austria, Belgium, Croatia, Denmark, Estonia, Finland, Germany, Iceland, Ireland, Lithuania, Luxembourg, Netherlands, Norway, Poland, Portugal, Slovenia, Sweden and United Kingdom. -Each Collaborative Research Project (CRP) must comprise at least three Principal Investigators, each based in an eligible university or a research institute in a different HERA JRP country. -Each participating researcher (e.g. senior, post-doc, Ph.D.) must be based at an eligible institution and be considered eligible for funding by the funding organisation of the HERA JRP country where he/she works. -The PI status is not limited to researchers at any specific career stage after Ph.D., although in some countries applicants with equivalent research experience are also eligible to apply.