The author considers the localizations of torsion-free Abelian groups, more precisely, the localizations of free groups, of cotorsion-free groups, and of finite rank Butler groups. For Abelian groups \(A,B\) a homomorphism \(\alpha\colon A\to B\) is said to be a `localization' of \(A\) if, for all \(f\colon A\to B\), there is a unique \(\varphi\colon B\to B\) such that \(f=\varphi\circ\alpha\). If \(F\) is a free Abelian group and \(R\) an \(E\)-ring then the homomorphism \(\alpha_{F,R}\colon F\to F\otimes R\) defined by \(\alpha(f)=f\otimes 1\) is always a localization of \(F\), called a `standard localization' of \(F\). However, it is shown in the article that, for any free Abelian group \(F\) of rank \(\kappa1\) such that \(G\) is \(p\)-reduced for at least four distinct primes \(p\) and \(\text{End}(G)=\mathbb{Z}\), it is shown that there exists an injective localization \(\alpha\colon G\to M\) such that \(M\) is a Butler group of rank \(2n\).