The UltraVISTA survey is the deepest of the VISTA public surveys,
providing near-infrared imaging over 1.5 square degrees of the COSMOS
field. The advent of deep imaging in the YJHKs bands over the field,
has revolutionised the study of the very brightest high-redshift
galaxies, has provided a detailed view of the evolving galaxy stellar
mass function from z ~ 0 to z ~ 4 and has identified the counterparts
of dust-enshrouded sub-mm galaxies. Furthermore, when combined with
the wealth of multi-wavelength imaging and spectroscopic datasets
currently available in the COSMOS field, the UltraVISTA imaging has a
strong community and legacy value. I will present an overview of the
UltraVISTA survey design and they key discoveries enabled by the
imaging, both from recently published works and in future synergies.