We prove that, given p > max 2n n+2 , 1 , the nonnegative almost minimizers of the nonlinear free boundary functional J p (u, Ω) := ˆΩ |∇u(x)| p + χ {u>0} (x) dx are Lipschitz continuous.The setting of almost minimizers is also classical in the calculus of variations (dating back, at least up to a certain extent, to a famous sentence in Leibniz's Specimen Geometriae Luciferae, probably written in the mid-1690s, "pro minimis adhiberi possunt quasi minima", that is "the almost minimizers can be exploited in place of minimizers").More specifically, the mathematical setting that we consider here goes as follows. Let Ω ⊂ R n be a given domain and p > max 2n n+2 , 1 . We consider the energy functionalThe condition that u is nonnegative corresponds, in the framework of free boundary problems, to considering "one-phase" solutions (solutions which may change sign being related to "twophase" problems).The precise notion of almost minimizers that we use in this paper is the following one: Definition 1.1. Let κ 0 and β > 0. We say that u ∈ W 1,p (Ω) is an almost minimizer for J p in Ω, with constant κ and exponent β, if u 0 a.e. in Ω andfor every ball B ̺ (x) such that B ̺ (x) ⊂ Ω and for every v ∈ W 1,p (B ̺ (x)) such that v = u on ∂B ̺ (x) in the sense of the trace.In some sense, Definition 1.1 is one of the possible modern formalizations of Leibniz's initial intuition reported at the beginning of this paper: namely, almost minimizers are natural objects to look at, for instance, to deal with minimizers of "perturbed" functionals. As a concrete example, if we considerfor a function Φ : R → [0, 1] with Φ = 0 in (−∞, 0], we readily see that J p (u, B r (x)) J p (u, B r (x)) andAccordingly, a minimizer for the "complicated" functional J p turns out to be an almost minimizer for the "simpler" functional J p .As usual, the constants depending only on n and p are called universal. If u is an almost minimizer, the structural constants may depend on κ and β as well.