Nanotechnology, and in particular the molecular manufacturing and nanoassembler concepts first put forward by K Eric Drexler  in the eighties, have been lauded as key enabling technologies to advance the human condition. At the core of this approach is the manipulation of single atoms and molecules using computer-controlled actuators or probes, which he argues will enable the assembly of "virtually anything" from basic raw materials . Widely decried in both the academic scientific community and in a variety of popular science publications and media , this form of molecular nanotechnology (MNT) has thus yet to be explored or tested experimentally. Nevertheless, at the core of this approach there is a demonstrably valid idea: the controlled positioning and manipulation of single atoms and molecules using, for example, scanning probe microscopes.
I will critically assess MNT from the perspective of an experimental nanoscientist , focussing in particular on the aims and objectives of a recently-funded programme of work  on computer-controlled assembly of diamond nanostructures, e.g. via mechanosynthesis .