Testing dark energy with supernovae

The use of Type la Supernovae as cosmic standard candles pose still perhaps the most direct way to probe the Cosmic acceleration history. In this contribution we will review the present status of Supernova cosmology. We will focus on current observations and what they can tell us about the properties of Dark Energy, i.e. our (in-)ability to distinguish dark energy models from cosmological constant. In the last part we will give a brief outlook at what to expect from future surveys. (C) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim