The product development plan (PDP) consists of six distinct phases. The business proposal is composed during phase 0, usually taking results of basic research into consideration. Definition and feasibility studies are performed in phase 1, followed by design and verification in two separate phases (2a and 2b). Phase 3 involves validation, and the final phase, phase 4, comprises commercialization. To streamline this process, there is an initial business plan review (BPR) and subsequent phase reviews (P0R to P4R) after all phases. During phase 1, a product requirements document (PRD) is developed. The PRD takes into account all technical and medical needs this product should ultimately meet. The project decision may still lead to changes in the overall planning. New product introduction (NPI) is a distinct process (in parallel with the PDP) that focuses on the successful introduction of the new product. Whereas the PDP is mostly focused on technical and medical requirements, the NPI also takes customer requirements, market needs, pricing, medical–economic value and other parameters into account. For the NPI, similar reviews are planned during the process, which go straight from the business plan (BP) to launch planning (LP). At two stages, very important development decisions are taken. At the end of phase 1, an ‘OK’ is needed, as well at the end of phase 3. At these stages, labour-intense and costly further development stages will be agreed upon by the development team. The boxes below the planning schemes identify some of the most important parameters that are studied during the various stages of the PDP and NPI. Note that specific investigations and changes are continually being investigated at the various stages. The dashed line implies the possibility for a development process to still be aborted during these phases. From phase 2a onward this is much less likely to happen. KOLs, key opinion leaders; R&D, research and development.