Colour research is challenging in field conditions, colour (as a product of light) constantly shifts with the changing light source. In an absence of reliable factual information, guidance tends to be followed in a dogmatic manner and predominately without professional design input, leading to dull, monotonous and under-stimulating environments. This is acutely significant in mental healthcare environments. This practice-led colour design research aims to challenge conventional guidance by employing architectural design knowledge to make site specific wall paintings within public and circulation spaces. Published output from the first project, in a dementia ward, led directly to the invitation by the Healthcare Trust to undertake the second project, as a pilot for the NHS to consider extending the strategic colour design to further areas of the estate.