This paper outlines a new language and run-time technology offering formalised design and
effiecient implementation for highly concuurent dynamic systems. It is based on a careful combination
of ideas from Hoare’s CSP (giving compositional semantics, refinement and safety/liveness analysis) and
Milners’s pi-calculus (giving dynamic network construction and mobility). We have been experimenting
with systems developing as layered networks of self-organising neighbourhood-aware communicating
processes, with no need for advanced planning or centralised control. The work reported is part of
our TUNA (‘Theories Undepinning Nanite Assemblies’) project, in parnership with colleagues from
the Universities of York and Surry, which is investigating formal approaches to the capture of safe
emergent behaviour in highly complex systems. A particular study modelling artificial blood platelets
is described. The software technology scales to millions of processes per processor and distributes over
common multiprocssor clusters
