Sarah Cremin established CAST architecture with Emmett Scanlon in 2006.

In 2000, Sarah joined the studio of Herzog & de Meuron in Basel, Switzerland and worked as project architect on a number of projects in China and the US. These include 40 Bond, a recently completed apartment building for Ian Schrager in New York City, headquarters and exhibition space for Prada USA in a converted piano factory in New York City and the design of a masterplan for the city of Jinhua, Zhejiang province, China, at the invitation of conceptual artist Ai Weiwei.

In 1998, Sarah joined Gabellini Sheppard in New York City and worked as project architect on the restoration of a protected townhouse, the design and realisation of Grant Selwyn Gallery and the Nicole Farhi flagship store. Sarah worked on the exterior restoration of significant New York landmarks such as the Whitehall Building and Cooper Union while at Bone Levine Architects between 1995 and 1998.

Sarah graduated from University College Dublin with a BArch degree in 1994 and with an MArchSc degree in 1996. Sarah currently teaches design in the School of Architecture.

In 2008, Sarah joined Emmett as Irish correspondent for A10, the journal of New European Architecture.