A stalking horse is a figure used to test a concept or mount a challenge on behalf of a third party. If the idea proves viable or popular, the third party can then declare its interest and advance the concept with little risk of failure. If the concept fails, the third party will not be tainted by association with the failed concept and can either drop the idea completely or bide its time and wait until a better moment for launching an attack. The relationship between the stalking horse and third party is usually, but not always, hidden from the public. In many cases, the scheme is one-sided, with only party aware of the arrangement.

Sir Anthony John Charles Meyer, 3rd Baronet was a British soldier, diplomat, and Conservative and later Liberal Democrat politician, best known for standing against Margaret Thatcher for the party leadership in 1989. In spite of his staunch conservative views on economic policy, his passionate support of increased British integration into the European Union led to him becoming increasingly marginalised in Thatcher's Conservative Party.