Three theories of gravitation – general relativity, the chameleon and Horava gravity - are confronted with experiment, using standard and adapted post-Newtonian (PN) tools. The laboratory is provided by the Solar System, binary pulsars and future detections at gravitational wave observatories. We test Horava gravity by studying emission of gravitational radiation in the weak-field limit for PN sources using techniques that take full advantage of the parametrized post-Newtonian (PPN) formalism. In particular, we provide a generalization of Einstein's quadrupole formula and show that a monopole persists even in the limit in which the PPN parameters are identical to those of General Relativity. Based on a technique called non-relativistic General Relativity, we propose a phenomenological way to measure deviations from General Relativity coming from an unknown UV completion. Finally, we systematically show that the self-interacting chameleon at orders three and higher do not jeopardize the chameleon theory for Solar System type objects.