  This volume contains the accepted papers at the third Workshop on Membrane
Computing and Biologically Inspired Process Calculi, held in Bologna on 5th
September 2009. The papers are devoted to both membrane computing and
biologically inspired process calculi, as well as to other related formalisms.
The papers of this volume are selected by the programme committee due to their
quality and relevance; they have defined an exciting programme highlighting
interesting problems and stimulating the search for novel ways of describing
related biological phenomena. In addition, we had an invited talk given by Luca
Cardelli on a spatial process algebra for developmental biology. Membrane
systems were introduced as a class of distributed parallel computing devices
inspired by the observation that any biological system is a complex
hierarchical structure, with a flow of materials and information that underlies
their functioning. The emphasis is on the computational properties of the
model, and it makes use of automata, languages, and complexity theoretic tools.
On the other hand, certain calculi such as mobile ambients and brane calculi
work with similar notions (compartments, membranes). These calculi are used to
model and analyze the various biological systems. The workshop on Membrane
Computing and Biologically Inspired Process Calculi brings together researchers
working in these fields to present their recent work and discuss new ideas
concerning the formalisms, their properties and relationships.
