Glass micropipettes are precisely constructed microtools forming the basis of a variety of investigative and clinically relevant techniques. They are used extensively in basic cellular research as channels into cells. Through these channels, substances can be injected or cellular contents extracted.

The fact that extremely high-quality microtools are available commercially should not necessarily discourage users from investigating the viability of making their own. The advantages are that the tools can be made on demand to one's own specifications, which can be far cheaper in the long run. In the early days of commercially available microtools, there were problems with continuity of supply and issues over quality. Nowadays, this does not seem to be such a problem (the market is becoming increasingly competitive), but lines of supply might still be intermittent in some parts of the world. Additionally, some more experienced and senior embryologists tend to consider microtool-making as a sort of rite of passage to which every newcomer to microinjection must be subjected. Certainly, while new techniques in micromanipulation continue to develop, new microtools need to be developed alongside, and manufacturers will usually start to mass-produce microtools only once it becomes clear that there is enough demand.

Whatever the reason for considering tool-making, it is still distinctly possible that embryologists will find themselves faced with such a task. While the techniques involved are not the easiest to master (many hours of practice may be necessary), they are not impossible if they are developed slowly and carefully, as outlined below.