  Within the framework of the effective field theory approach to the
post-Newtonian approximation to General Relativity, we report the so far
missing G^3 and G^4 sectors of the conservative two body dynamics at fourth
perturbative order for non-spinning compact objects. Following the standard
procedure, the exchange of gravitational interaction is integrated out to
obtain a systematic expansion in terms of Feynman graphs. Building on this
result and on previously obtained ones, we are able to write the local-in-time
regularized Lagrangian at fourth post-Newtonian order, which is in agreement
with results previously computed with other methods.
