In August 1998 a new European research program named extreme ultraviolet concept lithography development system (EUCLIDES) was started. The program, headed by ASM Lithography (ASML), partnered by Carl Zeiss and Oxford Instruments, is evaluating extreme ultraviolet lithography (EUVL) as a viable lithographic solution for resolutions of 70 nm and smaller. In this article a summary of program objectives and. status will be given, followed by an overview of recent highlights obtained by the various program partners and subcontractors. Results of the system architecture study will be presented. These include the (preliminary) results of the comparison study between laser plasma and synchrotron sources in terms of throughput and cost-of-ownership. A novel technique will be presented which mitigates resist outgassing without the need of a window between the projection optics and the wafer. Using this idea the EUV flux on the wafer can be doubled hence increasing the throughput. An EUVL test bench, containing an EUV interferometer is under construction. The test bench contains an operational water droplet laser plasma source. Experimental results will be presented. Part of the program focuses on optical and mechanical design, substrate fabrication, metrology, and multilayer coatings. Most recent results on coatings and optical substrate manufacturing will be presented.