diff --git a/src/bin/cargo.rs b/src/bin/cargo.rs
index a0b024f7bee..09c2ec2072e 100644
--- a/src/bin/cargo.rs
+++ b/src/bin/cargo.rs
@@ -62,6 +62,7 @@ macro_rules! each_subcommand( ($macro:ident) => ({
     $macro!(login)
     $macro!(new)
     $macro!(package)
+    $macro!(pkgid)
     $macro!(read_manifest)
     $macro!(run)
     $macro!(test)
diff --git a/src/bin/pkgid.rs b/src/bin/pkgid.rs
new file mode 100644
index 00000000000..48e4b6636e7
--- /dev/null
+++ b/src/bin/pkgid.rs
@@ -0,0 +1,52 @@
+use docopt;
+
+use cargo::ops;
+use cargo::core::MultiShell;
+use cargo::util::{CliResult, CliError};
+use cargo::util::important_paths::{find_root_manifest_for_cwd};
+
+docopt!(Options, "
+Print a fully qualified package specification
+
+Usage:
+    cargo pkgid [options] [<spec>]
+
+Options:
+    -h, --help              Print this message
+    --manifest-path PATH    Path to the manifest to the package to clean
+    -v, --verbose           Use verbose output
+
+Given a <pkgid> argument, print out the fully qualified package id specifier.
+This command will generate an error if <pkgid> is ambiguous as to which package
+it refers to in the dependency graph. If no <pkgid> is given, then the pkgid for
+the local package is printed.
+
+This command requires that a lockfile is available and dependencies have been
+fetched.
+
+Example Package IDs
+
+           pkgid                  |  name  |  version  |          url
+    |-----------------------------|--------|-----------|---------------------|
+     foo                          | foo    | *         | *
+     foo:1.2.3                    | foo    | 1.2.3     | *
+     crates.io/foo                | foo    | *         | *://crates.io/foo
+     crates.io/foo#1.2.3          | foo    | 1.2.3     | *://crates.io/foo
+     crates.io/bar#foo:1.2.3      | foo    | 1.2.3     | *://crates.io/bar
+     http://crates.io/foo#1.2.3   | foo    | 1.2.3     | http://crates.io/foo
+
+",  flag_manifest_path: Option<String>, arg_spec: Option<String>)
+
+pub fn execute(options: Options,
+               shell: &mut MultiShell) -> CliResult<Option<()>> {
+    shell.set_verbose(options.flag_verbose);
+    let root = try!(find_root_manifest_for_cwd(options.flag_manifest_path.clone()));
+
+    let spec = options.arg_spec.as_ref().map(|s| s.as_slice());
+    let spec = try!(ops::pkgid(&root, spec, shell).map_err(|err| {
+      CliError::from_boxed(err, 101)
+    }));
+    println!("{}", spec);
+    Ok(None)
+}
+
diff --git a/src/bin/update.rs b/src/bin/update.rs
index 79bd754dea3..f2328a23a67 100644
--- a/src/bin/update.rs
+++ b/src/bin/update.rs
@@ -10,7 +10,7 @@ docopt!(Options, "
 Update dependencies as recorded in the local lock file.
 
 Usage:
-    cargo update [options] [<name>]
+    cargo update [options] [<spec>]
 
 Options:
     -h, --help              Print this message
@@ -21,22 +21,24 @@ Options:
 This command requires that a `Cargo.lock` already exists as generated by
 `cargo build` or related commands.
 
-If <name> is specified, then a conservative update of the lockfile will be
-performed. This means that only the dependency <name> will be updated. Its
-transitive dependencies will be updated only if <name> cannot be updated without
-updating dependencies.  All other dependencies will remain locked at their
-currently recorded versions.
+If <spec> is given, then a conservative update of the lockfile will be
+performed. This means that only the dependency specified by <spec> will be
+updated. Its transitive dependencies will be updated only if <spec> cannot be
+updated without updating dependencies.  All other dependencies will remain
+locked at their currently recorded versions.
 
-If <name> is not specified, then all dependencies will be re-resolved and
+If <spec> is not given, then all dependencies will be re-resolved and
 updated.
-",  flag_manifest_path: Option<String>, arg_name: Option<String>)
+
+For more information about package ids, see `cargo help pkgid`.
+",  flag_manifest_path: Option<String>, arg_spec: Option<String>)
 
 pub fn execute(options: Options, shell: &mut MultiShell) -> CliResult<Option<()>> {
     debug!("executing; cmd=cargo-update; args={}", os::args());
     shell.set_verbose(options.flag_verbose);
     let root = try!(find_root_manifest_for_cwd(options.flag_manifest_path));
 
-    ops::update_lockfile(&root, shell, options.arg_name, options.flag_aggressive)
+    ops::update_lockfile(&root, shell, options.arg_spec, options.flag_aggressive)
         .map(|_| None).map_err(|err| CliError::from_boxed(err, 101))
 }
 
diff --git a/src/cargo/ops/cargo_generate_lockfile.rs b/src/cargo/ops/cargo_generate_lockfile.rs
index 0c214a99b18..fbc65c9d361 100644
--- a/src/cargo/ops/cargo_generate_lockfile.rs
+++ b/src/cargo/ops/cargo_generate_lockfile.rs
@@ -1,4 +1,3 @@
-#![warn(warnings)]
 use std::collections::HashSet;
 use std::io::File;
 
diff --git a/src/cargo/ops/cargo_pkgid.rs b/src/cargo/ops/cargo_pkgid.rs
new file mode 100644
index 00000000000..3b39bb0e7d7
--- /dev/null
+++ b/src/cargo/ops/cargo_pkgid.rs
@@ -0,0 +1,25 @@
+use ops;
+use core::{MultiShell, Source, PackageIdSpec};
+use sources::{PathSource};
+use util::{CargoResult, human};
+
+pub fn pkgid(manifest_path: &Path,
+             spec: Option<&str>,
+             _shell: &mut MultiShell) -> CargoResult<PackageIdSpec> {
+    let mut source = try!(PathSource::for_path(&manifest_path.dir_path()));
+    try!(source.update());
+    let package = try!(source.get_root_package());
+
+    let lockfile = package.get_root().join("Cargo.lock");
+    let source_id = package.get_package_id().get_source_id();
+    let resolve = match try!(ops::load_lockfile(&lockfile, source_id)) {
+        Some(resolve) => resolve,
+        None => return Err(human("A Cargo.lock must exist for this command"))
+    };
+
+    let pkgid = match spec {
+        Some(spec) => try!(resolve.query(spec)),
+        None => package.get_package_id(),
+    };
+    Ok(PackageIdSpec::from_package_id(pkgid))
+}
diff --git a/src/cargo/ops/mod.rs b/src/cargo/ops/mod.rs
index 7ea99eb1dd0..67e30def8a7 100644
--- a/src/cargo/ops/mod.rs
+++ b/src/cargo/ops/mod.rs
@@ -12,6 +12,7 @@ pub use self::cargo_package::package;
 pub use self::cargo_upload::{upload, upload_configuration, UploadConfig};
 pub use self::cargo_upload::{upload_login, http_proxy, http_handle};
 pub use self::cargo_fetch::{fetch, resolve_and_fetch};
+pub use self::cargo_pkgid::pkgid;
 
 mod cargo_clean;
 mod cargo_compile;
@@ -25,3 +26,4 @@ mod cargo_test;
 mod cargo_package;
 mod cargo_upload;
 mod cargo_fetch;
+mod cargo_pkgid;