The IFMIF-DONES test systems (TS) gather the experimental facilities offered by the plant, as well as the ancillary systems providing supplies and services both to those facilities and the irradiation modules, the latter ones belonging to the TS, although being excluded from the scope of this article. The irradiation modules gather any system that will be irradiated behind the lithium target inside the test cell (TC). Therefore, the TC also houses the liquid Li target and the stripping reaction held between the latter and the D+ beam. The TC is described in section 2, addressing as well some detail (section 2.1) about transversal key aspects like safety, RAMI, maintenance and others, although the safety aspects are collected in a dedicated part (section 5). The vacuum vessel is described in sections 2.2.1 and 2.2.3, relevant outputs from seismic, thermo-structural and fluido-dynamics analyses being as well provided. The shielding blocks are described in section 2.2.2, the lining part covering the building cavity filled in section 2.2.4, the floor in section 2.2.5, and the uppermost part in section 2.2.6. Section 3 is fully dedicated to the TSs ancillaries, a summary description being included for each of the subsystems, as well as an overview of their functional requirements. Section 4 provides a functional description of the different facilities for complementary experiments, apart from the TC. Section 5 is focused on safety issues applicable not only to the TC but to all the TSs included in the present article. Next, the current guidelines are given for the alignment (section 6) of the in-vessel systems and the integrated commissioning inside the TC (section 7). Finally, section 8 collects the main conclusions about the current status of the design of the TSs, irradiation modules excluded.