Although Spyropoulos remained in Greece his entire life, he attained international recognition and acclaim. His early work comprised still lifes, landscapes and portraits, which he painted without commitment to any specific style. In particular, the depiction of nature provided him with an opportunity to study the issues of space and composition that most concerned him. His paintings are characterized initially by loosely connected planes with floating motifs and an anti-naturalistic pigment applied in small, luminous vertical brushstrokes. In the 1950s, nature was his constant source of inspiration. He conceived the image and interpreted its elements in a play of alternating light and dark colors, in which space loses its third dimension. Lines, colored areas and geometric planes composed his vision, which he expressed in an increasingly abstract fashion that reached total abstraction in the early 1960s. His painting became more esoteric; his placement of pigment on the canvas evolved into an existential event. From the light, bright hues, he moves into earth tones and darker shades from which emerge a cosmogonic explosion of reds, ochres and whites that rip through the space in a hurling of psychic forces and energy automatically conveyed to the viewer. Collage, overpainting, burning, and cutting increase the tension, recruiting all the forces, both psychic and intellectual.