The simplest living organism is composed of myriad chemical subsystems, each consisting of structurally complex biomolecules that interact in many ways; the properties of life emerge from these dense connections. Understanding how these interactions take place will help elucidate the foundations of biology, as well as enabling the design and creation of new chemical networks with targeted functions. Deciphering and designing chemical systems requires new tools to be developed, however. In this research programme, we will develop new means for engineering functional chemical systems based upon the use of guest-binding capsules. These hosts will respond to many different signals in predictable ways. Their responses will enable their guests to be transformed in new ways or pumped between phases using light. Chemical signals will enable hosts to be transformed reversibly or irreversibly, changing their guest binding properties so as to favour some guests and disfavour others, and catalysts will be released or taken up, accelerating or impeding catalysed transformations. Ultimately we will design systems where signal transduction occurs in complex cycles and feedback loops, allowing complex behaviour to emerge from abiological systems.