Cairo bindings, which are expected to follow the binding guidelines as closely as possible, are available for various languages:
Ada : CairoAda
C++ : cairomm
COM-Wrapper : aka "ActiveX-dll" ... easiest to use with VB5/6 or VBA, comes with cairo as a "satellite-dll" (compiled with StdCall-callingconvention) download-page: (a large VB-Democode-Tutorial is available there too)
Harbour : hbcairo
Haskell : hscairo
Java : org.freedesktop.cairo in java-gnome
Mono and .NET bindings (C# and any other CLS language) are bundled with the Mono distribution in the Mono.Cairo library.
Objective Caml : cairo-ocaml
Perl : cairo-perl
PHP : cairo-php
Prolog : PLcairo
Ruby : rcairo
Ypsilon Scheme ships with Cairo bindings
Digitalmars D: cairoD - simple wrapper for D direct C API
Since cairo is only a drawing library, it can be quite useful to integrate it with a graphical user interface toolkit.
FLTK has full cairo support (through "--enable-cairo" compile switch).
GTK+ 2.8+ has full support for cairo.