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+# Proxy
+
+HTTP CONNECT proxies are supported by default in gRPC. The proxy address can be
+specified by the environment variables HTTP_PROXY, HTTPS_PROXY and NO_PROXY (or
+the lowercase versions thereof).
+
+## Custom proxy
+
+Currently, proxy support is implemented in the default dialer. It does one more
+handshake (a CONNECT handshake in the case of HTTP CONNECT proxy) on the
+connection before giving it to gRPC.
+
+If the default proxy doesn't work for you, replace the default dialer with your
+custom proxy dialer. This can be done using
+[`WithDialer`](https://godoc.org/google.golang.org/grpc#WithDialer).
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