diff --git a/Cargo.lock b/Cargo.lock
index 23ff2ad8..96b6bd03 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -314,6 +314,16 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "core-foundation"
+version = "0.10.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b2a6cd9ae233e7f62ba4e9353e81a88df7fc8a5987b8d445b4d90c879bd156f6"
+dependencies = [
+ "core-foundation-sys",
+ "libc",
+]
+
 [[package]]
 name = "core-foundation-sys"
 version = "0.8.7"
@@ -724,7 +734,7 @@ dependencies = [
  "rand 0.10.2",
  "resolv-conf",
  "smallvec",
- "system-configuration",
+ "system-configuration 0.7.0",
  "thiserror 2.0.20",
  "tokio",
  "tracing",
@@ -922,8 +932,8 @@ checksum = "4d40460c0ce33d6ce4b0630ad68ff63d6661961c48b6dba35e5a4d81cfb48222"
 dependencies = [
  "socket2",
  "widestring",
- "windows-registry",
- "windows-result",
+ "windows-registry 0.6.1",
+ "windows-result 0.4.1",
  "windows-sys 0.61.2",
 ]
 
@@ -956,7 +966,7 @@ dependencies = [
  "simd_cesu8",
  "thiserror 2.0.20",
  "walkdir",
- "windows-link",
+ "windows-link 0.2.1",
 ]
 
 [[package]]
@@ -1025,7 +1035,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d7c4b02199fee7c5d21a5ae7d8cfa79a6ef5bb2fc834d6e9058e89c825efdc55"
 dependencies = [
  "cfg-if",
- "windows-link",
+ "windows-link 0.2.1",
 ]
 
 [[package]]
@@ -1260,7 +1270,7 @@ dependencies = [
  "libc",
  "redox_syscall",
  "smallvec",
- "windows-link",
+ "windows-link 0.2.1",
 ]
 
 [[package]]
@@ -1797,7 +1807,18 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a13f3d0daba03132c0aa9767f98351b3488edc2c100cda2d2ec2b04f3d8d3c8b"
 dependencies = [
  "bitflags",
- "core-foundation",
+ "core-foundation 0.9.4",
+ "system-configuration-sys",
+]
+
+[[package]]
+name = "system-configuration"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "501336eb7ba9e417300a6a0fa985721065467aa83a6dcf0422a8e43e4c0328fa"
+dependencies = [
+ "bitflags",
+ "core-foundation 0.10.1",
  "system-configuration-sys",
 ]
 
@@ -2311,15 +2332,32 @@ version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f0805222e57f7521d6a62e36fa9163bc891acd422f971defe97d64e70d0a4fe5"
 
+[[package]]
+name = "windows-link"
+version = "0.100.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9b39de7c7fe78858b0144c50c3fc000bab3be17d5e9b85b1053871693c7f7415"
+
 [[package]]
 name = "windows-registry"
 version = "0.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "02752bf7fbdcce7f2a27a742f798510f3e5ad88dbe84871e5168e2120c3d5720"
 dependencies = [
- "windows-link",
- "windows-result",
- "windows-strings",
+ "windows-link 0.2.1",
+ "windows-result 0.4.1",
+ "windows-strings 0.5.1",
+]
+
+[[package]]
+name = "windows-registry"
+version = "0.100.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a14b75dbbc0f2bb1ebbf6dcb6dc0035ae17f10ec280045d10fa27ad8874903b2"
+dependencies = [
+ "windows-link 0.100.0",
+ "windows-result 0.100.0",
+ "windows-strings 0.100.0",
 ]
 
 [[package]]
@@ -2328,7 +2366,16 @@ version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7781fa89eaf60850ac3d2da7af8e5242a5ea78d1a11c49bf2910bb5a73853eb5"
 dependencies = [
- "windows-link",
+ "windows-link 0.2.1",
+]
+
+[[package]]
+name = "windows-result"
+version = "0.100.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "44873a1ef61c85d5e2991db91fe656cfcf0731097e00dff1ac860f1cb3b752a0"
+dependencies = [
+ "windows-link 0.100.0",
 ]
 
 [[package]]
@@ -2337,7 +2384,16 @@ version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7837d08f69c77cf6b07689544538e017c1bfcf57e34b4c0ff58e6c2cd3b37091"
 dependencies = [
- "windows-link",
+ "windows-link 0.2.1",
+]
+
+[[package]]
+name = "windows-strings"
+version = "0.100.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6a70b590c684f1d2854f74999896f7c0558f1bdde62f599088599e20ea1d2f60"
+dependencies = [
+ "windows-link 0.100.0",
 ]
 
 [[package]]
@@ -2355,7 +2411,7 @@ version = "0.61.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ae137229bcbd6cdf0f7b80a31df61766145077ddf49416a728b02cb3921ff3fc"
 dependencies = [
- "windows-link",
+ "windows-link 0.2.1",
 ]
 
 [[package]]
@@ -2459,6 +2515,7 @@ dependencies = [
  "serde_json",
  "socket2",
  "sync_wrapper",
+ "system-configuration 0.8.0",
  "tokio",
  "tokio-btls",
  "tokio-socks",
@@ -2468,6 +2525,7 @@ dependencies = [
  "tower-http",
  "url",
  "webpki-root-certs",
+ "windows-registry 0.100.0",
  "wreq-rt",
 ]
 
diff --git a/Cargo.toml b/Cargo.toml
index 420648e3..10f0902b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -54,6 +54,7 @@ wreq = { version = "0.16.1", default-features = false, features = [
     "form",
     "json",
     "socks",
+    "system-proxy",
     "stream",
     "multipart",
     "cookies",
diff --git a/docs/source/guide/proxy.md b/docs/source/guide/proxy.md
index d9de68fe..a2b597b5 100644
--- a/docs/source/guide/proxy.md
+++ b/docs/source/guide/proxy.md
@@ -36,6 +36,11 @@ async def main():
 asyncio.run(main())
 ```
 
+By default, a client without `proxies` uses the system proxy: the
+`HTTP_PROXY`, `HTTPS_PROXY`, `ALL_PROXY` and `NO_PROXY` environment variables
+(and their lowercase forms), plus the operating system proxy settings on macOS
+and Windows.
+
 For direct connections that ignore environment and system proxy settings, use
 `Client(no_proxy=True)`. This also clears proxies configured on that client.
 To exclude hosts from a particular proxy, pass an exclusion list when creating