An exciting new area of chemistry involves making new "smart" materials that can interact with their environment to produce soft robots. These pioneering systems can respond to a huge range of inputs with large deformations to perform tasks that are difficult or impossible to achieve with traditional technology. Smart materials capable of 'mechanical intelligence' - the ability to at once sense and respond to a specific stimulus in a controlled and defined manner, without the aid of electronics or additional control systems - has the potential to revolutionise biomedical devices. Imagine artificial muscles that can detect small changes in their environment to power artificial limbs, or surgical instruments that can sense and move around delicate areas of the body. The chemistry used to develop these smart materials can be used to tune specific properties - making the individual materials perfect for the specific task in hand. PhotoSMART aims to do just that, to produce an entirely new class of smart materials that move in response to light, and whose properties can be tuned through changing the chemistry of the system. Crucially these smart materials will work using visible light rather than damaging UV light - something that is vital to applications in biomedical environments. Certain organic molecules respond to light by producing huge rearrangements in their chemical structure, causing molecular-scale movement. The exact wavelength at which they respond can be tuned by changing the chemistry of the molecule. PhotoSMART will involve integrating this switching functionality with flexible polymer materials that can be readily engineered. Subsequently, the active polymer materials will be carefully structured to amplify the molecular-scale motion to produce large movements that can perform useful tasks in the world around us.