The central themes of the degree are lightness value of colour and the valeur keys. The objective was the definition of the individual valeur keys and use of the art theory for the creation of my own paintings. In theoretical part of degree I defined the concept of colour and elementary dimensions of colour: hue, lightness and saturation, and the expressiveness of individual colours. I addressed concepts of light and dark color contrast and valeur, value. I described the criteria determining the valeur keys and defined the individual valeur keys: high major, high minor, middle major, middle minor, low major and low minor. I looked into role of colour in modernistic painting, I concentrated on fields of modernistic painting where the main carrier of expression is colour and where we can speak about the mood impression of colour. Here I concentrated on painting practice of Henri Matisse and Mark Rothko and placed examples of their art work to the individual valeur keys. I painted six art works in the practical part of degree - one for each of the valeur keys. When painting, I concentrated on the emotional component, on the expression of current mood. Made art works are abstract, the emphasis is on the gesture. By focusing on the conveyance of current, internal, I balanced the rational approach for the preparation of work.