15. A method, comprising: receiving, by a first computing device, a search query from a second computing device; generating, by the first computing device, a set of search results by executing a search based at least in part on the search query; selecting, by the first computing device, a subset of a plurality of supplemental content providers based at least in part on respective relevancies of the plurality of supplemental content providers to the search query; selecting, by the first computing device, the subset of the plurality of supplemental content providers further based at least in part on a compatibility rule that defines compatibility between supplemental content from a first supplemental content provider and supplemental content from a second supplemental content provider as permission to be rendered together in a search results page; selecting, by the first computing device, the subset of the plurality of supplemental content providers further based at least in part on relative immediate monetary values associated with the plurality of supplemental content providers; selecting, by the first computing device, the subset of the plurality of supplemental content providers further based at least in part on relative downstream business values associated with the plurality of supplemental content providers; generating, by the first computing device, the search results page configured to present supplemental content from the subset of the plurality of supplemental content providers in association with the set of search results; and sending, by the first computing device, data encoding the search results page to the second computing device.
15. A method, comprising: receiving, by a first computing device, a search query from a second computing device; generating, by the first computing device, a set of search results by executing a search based at least in part on the search query; selecting, by the first computing device, a subset of a plurality of supplemental content providers based at least in part on respective relevancies of the plurality of supplemental content providers to the search query; selecting, by the first computing device, the subset of the plurality of supplemental content providers further based at least in part on a compatibility rule that defines compatibility between supplemental content from a first supplemental content provider and supplemental content from a second supplemental content provider as permission to be rendered together in a search results page; selecting, by the first computing device, the subset of the plurality of supplemental content providers further based at least in part on relative immediate monetary values associated with the plurality of supplemental content providers; selecting, by the first computing device, the subset of the plurality of supplemental content providers further based at least in part on relative downstream business values associated with the plurality of supplemental content providers; generating, by the first computing device, the search results page configured to present supplemental content from the subset of the plurality of supplemental content providers in association with the set of search results; and sending, by the first computing device, data encoding the search results page to the second computing device. 18. The method of claim 15 , further comprising generating, by the first computing device, a relative layout for the search results page based at least in part on respective relevancies of the subset of the plurality of supplemental content providers.