This article deals with the way colours in a room affect each other through contrast effects and reflections. The study presented is based an the visual observations of the colour appearance of three inherent colours in a sequence of experimental situations. My point of departure was a yellow, blue, and red room. The room had distinctly different colour appearances of the same inherent colours when observed at different locations. The effects of both contrasts and reflections were evident. However, reflection effects seemed to dominate the situation. In a study of small experimental rooms, different combinations of the same three inherent colours were systematically tested Comparisons were made to examine the differences in colour appearance between monochromatic rooms and multicoloured rooms with varying colour schemes. The illumination was kept stable. In the cases studied it was obvious how the colours in the two-coloured rooms became more alike or "neutralized each other." The contrast strengthening between abutting areas an the same level had distinct significance for colour appearance and perception of space. However, not in such a way that the perceived colour differences became larger in the two-coloured roam than between each monochromatic rooms.