A classic example of Piet Mondrian's Neoplasticism, featuring a rhythmic grid of black lines and primary colours.

Trafalgar Square, painted by Piet Mondrian between 1939 and 1943, represents the artist's mature exploration of Neoplasticism. During his residence in London, Mondrian began to shift his approach to the grid, moving away from the strict black lines that defined his earlier Parisian works. In this composition, the black lines appear to stop short of the canvas edge, creating a sense of openness and rhythmic movement. The work is structured by a series of vertical and horizontal lines that intersect to form rectangular planes of varying sizes. Within this framework, Mondrian employs his signature palette of primary colours: red, blue, and yellow, set against a ground of white and black. The placement of these colours is deliberate, balancing the visual weight across the surface. The yellow block in the upper left corner and the smaller red and blue accents create a dynamic equilibrium. Unlike his earlier works, where the lines acted as containers for the colour, here the lines and planes interact with greater fluidity. The title refers to the artist's time in London, yet the work remains entirely abstract, focusing on the universal principles of harmony and proportion. The surface is flat, rejecting any illusion of three-dimensional space in favour of a direct, objective visual experience. This piece demonstrates the artist's pursuit of a pure, non-representational art form that seeks to express the underlying order of the universe through geometric precision and primary colour.