diff --git a/src/cargo/core/manifest.rs b/src/cargo/core/manifest.rs
index f0ce165f8c0..552455acc0f 100644
--- a/src/cargo/core/manifest.rs
+++ b/src/cargo/core/manifest.rs
@@ -322,6 +322,7 @@ impl Target {
     }
 
     pub fn name(&self) -> &str { &self.name }
+    pub fn crate_name(&self) -> String { self.name.replace("-", "_") }
     pub fn src_path(&self) -> &Path { &self.src_path }
     pub fn metadata(&self) -> Option<&Metadata> { self.metadata.as_ref() }
     pub fn kind(&self) -> &TargetKind { &self.kind }
@@ -332,6 +333,10 @@ impl Target {
     pub fn for_host(&self) -> bool { self.for_host }
     pub fn benched(&self) -> bool { self.benched }
 
+    pub fn allows_underscores(&self) -> bool {
+        self.is_bin() || self.is_example() || self.is_custom_build()
+    }
+
     pub fn is_lib(&self) -> bool {
         match self.kind {
             TargetKind::Lib(_) => true,
diff --git a/src/cargo/ops/cargo_rustc/context.rs b/src/cargo/ops/cargo_rustc/context.rs
index 87e1092e3ca..18ce154102e 100644
--- a/src/cargo/ops/cargo_rustc/context.rs
+++ b/src/cargo/ops/cargo_rustc/context.rs
@@ -282,9 +282,10 @@ impl<'a, 'b: 'a> Context<'a, 'b> {
     /// Returns the file stem for a given target/profile combo
     pub fn file_stem(&self, target: &Target, profile: &Profile) -> String {
         match self.target_metadata(target, profile) {
-            Some(ref metadata) => format!("{}{}", target.name(),
+            Some(ref metadata) => format!("{}{}", target.crate_name(),
                                           metadata.extra_filename),
-            None => target.name().to_string(),
+            None if target.allows_underscores() => target.name().to_string(),
+            None => target.crate_name().to_string(),
         }
     }
 
diff --git a/src/cargo/ops/cargo_rustc/custom_build.rs b/src/cargo/ops/cargo_rustc/custom_build.rs
index 82ea558583e..6e3d32711b5 100644
--- a/src/cargo/ops/cargo_rustc/custom_build.rs
+++ b/src/cargo/ops/cargo_rustc/custom_build.rs
@@ -46,9 +46,7 @@ pub fn prepare(pkg: &Package, target: &Target, req: Platform,
     };
 
     // Building the command to execute
-    let profile = cx.build_script_profile(pkg.package_id());
-    let to_exec = try!(cx.target_filenames(target, profile))[0].clone();
-    let to_exec = script_output.join(&to_exec);
+    let to_exec = script_output.join(target.name());
 
     // Start preparing the process to execute, starting out with some
     // environment variables. Note that the profile-related environment
diff --git a/src/cargo/ops/cargo_rustc/mod.rs b/src/cargo/ops/cargo_rustc/mod.rs
index d32d7593df0..542eeb1236e 100644
--- a/src/cargo/ops/cargo_rustc/mod.rs
+++ b/src/cargo/ops/cargo_rustc/mod.rs
@@ -328,9 +328,15 @@ fn rustc(package: &Package, target: &Target, profile: &Profile,
         let pass_l_flag = target.is_lib() || !package.targets().iter().any(|t| {
             t.is_lib()
         });
+        let do_rename = target.allows_underscores() && !profile.test;
+        let real_name = target.name().to_string();
+        let crate_name = target.crate_name();
 
-        let rustc_dep_info_loc = root.join(&cx.file_stem(target, profile))
-                                     .with_extension("d");
+        let rustc_dep_info_loc = if do_rename {
+            root.join(&crate_name)
+        } else {
+            root.join(&cx.file_stem(target, profile))
+        }.with_extension("d");
         let dep_info_loc = fingerprint::dep_info_loc(cx, package, target,
                                                      profile, kind);
         let cwd = cx.config.cwd().to_path_buf();
@@ -363,7 +369,20 @@ fn rustc(package: &Package, target: &Target, profile: &Profile,
                 human(format!("Could not compile `{}`.", name))
             }));
 
-            try!(fs::rename(&rustc_dep_info_loc, &dep_info_loc));
+            if do_rename && real_name != crate_name {
+                let dst = root.join(&filenames[0]);
+                let src = dst.with_file_name(dst.file_name().unwrap()
+                                                .to_str().unwrap()
+                                                .replace(&real_name, &crate_name));
+                try!(fs::rename(&src, &dst).chain_error(|| {
+                    human(format!("could not rename crate {:?}", src))
+                }));
+            }
+
+            try!(fs::rename(&rustc_dep_info_loc, &dep_info_loc).chain_error(|| {
+                human(format!("could not rename dep info: {:?}",
+                              rustc_dep_info_loc))
+            }));
             try!(fingerprint::append_current_dir(&dep_info_loc, &cwd));
 
             Ok(())
@@ -482,7 +501,7 @@ fn rustdoc(package: &Package, target: &Target, profile: &Profile,
     rustdoc.arg(&root_path(cx, package, target))
            .cwd(cx.config.cwd())
            .arg("-o").arg(&cx_root)
-           .arg("--crate-name").arg(target.name());
+           .arg("--crate-name").arg(&target.crate_name());
 
     match cx.resolve.features(package.package_id()) {
         Some(features) => {
@@ -565,7 +584,7 @@ fn build_base_args(cx: &Context,
     // TODO: Handle errors in converting paths into args
     cmd.arg(&root_path(cx, pkg, target));
 
-    cmd.arg("--crate-name").arg(target.name());
+    cmd.arg("--crate-name").arg(&target.crate_name());
 
     for crate_type in crate_types.iter() {
         cmd.arg("--crate-type").arg(crate_type);
@@ -696,7 +715,7 @@ fn build_deps_args(cmd: &mut CommandPrototype,
         for filename in try!(cx.target_filenames(target, profile)).iter() {
             if filename.ends_with(".a") { continue }
             let mut v = OsString::new();
-            v.push(target.name());
+            v.push(&target.crate_name());
             v.push("=");
             v.push(layout.root());
             v.push(&path::MAIN_SEPARATOR.to_string());
diff --git a/src/cargo/util/toml.rs b/src/cargo/util/toml.rs
index 52148d4ce03..23d255b79b5 100644
--- a/src/cargo/util/toml.rs
+++ b/src/cargo/util/toml.rs
@@ -395,16 +395,17 @@ impl TomlManifest {
                     ManyOrOne::Many(..) => used_deprecated_lib = true,
                     _ => {}
                 }
-                libs.as_slice().iter().map(|t| {
-                    if layout.lib.is_some() && t.path.is_none() {
+                try!(libs.as_slice().iter().map(|t| {
+                    try!(validate_target_name(t));
+                    Ok(if layout.lib.is_some() && t.path.is_none() {
                         TomlTarget {
                             path: layout.lib.as_ref().map(|p| PathValue::Path(p.clone())),
                             .. t.clone()
                         }
                     } else {
                         t.clone()
-                    }
-                }).collect()
+                    })
+                }).collect::<CargoResult<Vec<_>>>())
             }
             None => inferred_lib_target(&project.name, layout),
         };
@@ -413,34 +414,48 @@ impl TomlManifest {
             Some(ref bins) => {
                 let bin = layout.main();
 
-                bins.iter().map(|t| {
-                    if bin.is_some() && t.path.is_none() {
+                try!(bins.iter().map(|t| {
+                    try!(validate_target_name(t));
+                    Ok(if bin.is_some() && t.path.is_none() {
                         TomlTarget {
                             path: bin.as_ref().map(|&p| PathValue::Path(p.clone())),
                             .. t.clone()
                         }
                     } else {
                         t.clone()
-                    }
-                }).collect()
+                    })
+                }).collect::<CargoResult<Vec<_>>>())
             }
             None => inferred_bin_targets(&project.name, layout)
         };
 
         let examples = match self.example {
-            Some(ref examples) => examples.clone(),
+            Some(ref examples) => {
+                for example in examples {
+                    try!(validate_target_name(example));
+                }
+                examples.clone()
+            }
             None => inferred_example_targets(layout),
         };
 
         let tests = match self.test {
-            Some(ref tests) => tests.clone(),
+            Some(ref tests) => {
+                for test in tests {
+                    try!(validate_target_name(test));
+                }
+                tests.clone()
+            }
             None => inferred_test_targets(layout),
         };
 
         let benches = if self.bench.is_none() || self.bench.as_ref().unwrap().is_empty() {
             inferred_bench_targets(layout)
         } else {
-            self.bench.as_ref().unwrap().iter().map(|t| t.clone()).collect()
+            try!(self.bench.as_ref().unwrap().iter().map(|t| {
+                try!(validate_target_name(t));
+                Ok(t.clone())
+            }).collect::<CargoResult<Vec<_>>>())
         };
 
         // processing the custom build script
@@ -529,6 +544,15 @@ impl TomlManifest {
     }
 }
 
+fn validate_target_name(target: &TomlTarget) -> CargoResult<()> {
+    if target.name.contains("-") {
+        Err(human(format!("target names cannot contain hyphens: {}",
+                          target.name)))
+    } else {
+        Ok(())
+    }
+}
+
 fn process_dependencies<F>(cx: &mut Context,
                            new_deps: Option<&HashMap<String, TomlDependency>>,
                            mut f: F) -> CargoResult<()>
diff --git a/tests/test_cargo_compile.rs b/tests/test_cargo_compile.rs
index a78c478e954..e200af5bd88 100644
--- a/tests/test_cargo_compile.rs
+++ b/tests/test_cargo_compile.rs
@@ -1653,3 +1653,37 @@ test!(cyclic_deps_rejected {
 cyclic package dependency: package `foo v0.0.1 ([..])` depends on itself
 "));
 });
+
+test!(dashes_to_underscores {
+    let p = project("foo")
+        .file("Cargo.toml", r#"
+            [package]
+            name = "foo-bar"
+            version = "0.0.1"
+            authors = []
+        "#)
+        .file("src/lib.rs", "")
+        .file("src/main.rs", "extern crate foo_bar; fn main() {}");
+
+    assert_that(p.cargo_process("build").arg("-v"),
+                execs().with_status(0));
+    assert_that(&p.bin("foo-bar"), existing_file());
+});
+
+test!(dashes_in_crate_name_bad {
+    let p = project("foo")
+        .file("Cargo.toml", r#"
+            [package]
+            name = "foo"
+            version = "0.0.1"
+            authors = []
+
+            [lib]
+            name = "foo-bar"
+        "#)
+        .file("src/lib.rs", "")
+        .file("src/main.rs", "extern crate foo_bar; fn main() {}");
+
+    assert_that(p.cargo_process("build").arg("-v"),
+                execs().with_status(101));
+});
diff --git a/tests/test_cargo_compile_custom_build.rs b/tests/test_cargo_compile_custom_build.rs
index 8745d409c71..093942e866f 100644
--- a/tests/test_cargo_compile_custom_build.rs
+++ b/tests/test_cargo_compile_custom_build.rs
@@ -33,7 +33,7 @@ test!(custom_build_script_failed {
                 execs().with_status(101)
                        .with_stdout(format!("\
 {compiling} foo v0.5.0 ({url})
-{running} `rustc build.rs --crate-name build-script-build --crate-type bin [..]`
+{running} `rustc build.rs --crate-name build_script_build --crate-type bin [..]`
 {running} `[..]build-script-build[..]`
 ",
 url = p.url(), compiling = COMPILING, running = RUNNING))
@@ -760,7 +760,7 @@ test!(build_cmd_with_a_build_cmd {
     --out-dir [..]target[..]deps --emit=dep-info,link \
     -L [..]target[..]deps -L [..]target[..]deps`
 {compiling} foo v0.5.0 (file://[..])
-{running} `rustc build.rs --crate-name build-script-build --crate-type bin \
+{running} `rustc build.rs --crate-name build_script_build --crate-type bin \
     -C prefer-dynamic -g \
     --out-dir [..]build[..]foo-[..] --emit=dep-info,link \
     -L [..]target[..]debug -L [..]target[..]deps \