Electroweak precision tests: present and future

After a brief summary of the current status of precision tests of the electroweak Standard Model, the new insights on electroweak physics expected from the LHC will be discussed. These include measurements of classic precision quantities, as well as genuine high-energy tests. It will be illustrated how existing e+e- data and future results from the LHC probe possible new physics effects in a complementary way. Finally, the improvements of electroweak precision tests from a future high-luminosity e+e- collider will be discussed and compared to existing theory predictions, in particular elucidating the available methods for computing high-order loop corrections and estimating their uncertainty.