In the 17th century a new kind of scientific instrument emerged: the Philosophical Instrument. With these devices nothing was measured, but what they revealed gave food for thought. The microscope was one of these philosophical instruments that provided insight into a new, previously unknown microworld. Although the microscope was developed from the telescope in the late 1610s, the instrument only came to fruition in the late 1650s. The instrument became even more successful after the launch of the single lens microscope around 1660. The major Dutch researcher Antony van Leeuwenhoek and many other early microscopists made their own microscopes, which were never sold to the public. However the sensational discoveries of several of these microscopists in the 1670s created a public demand for such microscopes, which demand generated the emergence of professional microscope makers. In this new market Dutch, French, German and English instrument makers tried to get their share. In this presentation will be examined how this professional production and trade of microscopes evolved in the early Dutch Republic, and how the network of ownership of these instruments and their makers functioned to bring a locally developed product to a wider audience.