EasyHook!

Deviare is a professional open source hooking engine for instrumenting arbitrary Win32 functions, COM objects, and functions which symbols are located in program databases (PDBs). It can intercept unmanaged code in 32-bit and 64-bit applications. It is implemented as a COM component, so it can be integrated with all the programming languages which support COM, such as C/C++, VB, C#, Delphi, and Python.

Microsoft Research Detours v3 Professional is a library for instrumenting arbitrary Win32 functions. Detours intercepts Win32 functions by re-writing the in-memory code for target functions. The Detours package also contains utilities to attach arbitrary DLLs and data segments to any Windows application binary.

madCodeHook offers everything you need to hook code (mostly APIs) in all 32 and 64 bit Windows operating systems from Windows 95 to Windows 10. You can choose whether you want to hook APIs in your own process, or in a specific target process, or system wide.