Last night, while looking through my copy of Neue Grafik/New Graphic Design/Graphisme actual, I discovered the wonderful work of Rosmarie Tissi. She was born in Switzerland, then studied design in Zürich, and has been a member of AGI since 1974. In 1968, she formed O&T studio with Siegfried Odermatt.
I really love how she blends the swiss style, with a more abstract style using a lot of geometric shapes. You can see more of her work here, here, here, here and here.