This workshop follows in the tradition of its predecessors, WAMS and WAMSDO, organized in the framework of previous FP6-CARE and FP7-EuCARD programs, and will be the first of a series of workshops dedicated to High Temperature Superconductors technology development for Accelerator Magnets. The goal of the FP7-EuCARD-2 provides a natural focus for this series of workshops: the design and construction of an HTS dipole capable of boosting the field of an accelerator (collider) dipole from 15 T to about 20 T, with a suitable margin. This, in view of the new large HEP project called Future Circular Collider. This series of workshops will also inform on themes relative to other types of accelerators including an all-HTS 5 T dipole or fast cycling accelerator HTS magnets for the FCC Injector chain and other synchrotron type accelerators. We aim to provide a forum where material scientists, conductor designers, and magnet engineers exchange ideas, information, compare various lines of development for various projects, and try to single out the most important needs for improvements. A strong participation from Industry is foreseen in order to promote industrialization. The workshop should help build synergies among various programs, favouring the exchange of ideas and people among various labs and institutions. The format will be more of a discussion workshop rather than a mini-conference. We do not foresee proceedings. However, the organizers will provide a document of synthesis that, besides summarising the most important progress reported in the workshop, should also provide guidelines and useful recommendations endorsed by the main actors. This can be used to reinforce the position of each participant regarding the respective funding agency by providing a unitary frame for R&D and common, agreed goals. WAMHTS-1 in Hamburg will be focussed on conductor development. This includes material and single tape/wire optimization as well as material characterization. However, the main accent will be on multiple tape/strand cable, i.e., the conductor unit that is used for manufacturing practical collider magnets. Conductor is the crossroad where material basic properties, tapes/strands engineering, insulation issues and magnet design and technology must have their optimization point in order to maximize the performance of the final product. The next workshop will focus on different topics, like magnet design and coil technology. This workshop is by invitation only.