Karen paints with a bold and sure style. Her palette is often a daring one in which rich and vibrant colours are dominant. Rieger also uses a stunning darker palette in both her figurative and still-life pieces.

Often in her canvases, mysterious serene women evoke imaginings about who they might be or what they may be thinking. Opulent still life paintings fill the canvases with overblown roses and intricate wrought-iron tables or jardinières. Also note the ancient motifs and intriguing patterns that the artist uses to great advantage in her work.

Rieger attended the Ontario College of Art, The Art Centre, Central Technical School and the University of Toronto, Liberal Arts Programme. In 1994 she was elected member of the Canadian Society of Painters in Watercolour.

Karen is represented in several galleries within Canada. Her paintings hang in many collections in Canada, the U.S.A., Europe and the Bahamas.