diff --git a/README.rdoc b/README.rdoc
index 52c01df..b8a6514 100644
--- a/README.rdoc
+++ b/README.rdoc
@@ -65,7 +65,7 @@ See the git log comments.
 
 * More tests.
 
-* Implement Admin.
+* Implement the rest of the Admin interface.
 
 * Study src/main/ed/db/{dbcollection,dbcursor,db}.js and ByteEncoder.java in
   the Babble code. That's what I should be writing to.
diff --git a/lib/mongo.rb b/lib/mongo.rb
index 6b300b4..d99689d 100644
--- a/lib/mongo.rb
+++ b/lib/mongo.rb
@@ -4,3 +4,4 @@ require 'mongo/message'
 require 'mongo/db'
 require 'mongo/cursor'
 require 'mongo/collection'
+require 'mongo/admin'
diff --git a/lib/mongo/admin.rb b/lib/mongo/admin.rb
new file mode 100644
index 0000000..cb3a955
--- /dev/null
+++ b/lib/mongo/admin.rb
@@ -0,0 +1,78 @@
+# --
+# Copyright (C) 2008-2009 10gen Inc.
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Affero General Public License, version 3, as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License
+# for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+# ++
+
+require 'mongo/util/ordered_hash'
+
+module XGen
+  module Mongo
+    module Driver
+
+      # Provide administrative database methods: those having to do with
+      # profiling and validation.
+      class Admin
+
+        def initialize(db)
+          @db = db
+        end
+
+        # Return the current database profiling level.
+        def profiling_level
+          oh = OrderedHash.new
+          oh[:profile] = -1
+          doc = @db.db_command(oh)
+          raise "Error with profile command: #{doc.inspect}" unless @db.ok?(doc) && doc['was'].kind_of?(Numeric)
+          case doc['was'].to_i
+          when 0
+            :off
+          when 1
+            :slow_only
+          when 2
+            :all
+          else
+            raise "Error: illegal profiling level value #{doc['was']}"
+          end
+        end
+
+        # Set database profiling level to :off, :slow_only, or :all.
+        def profiling_level=(level)
+          oh = OrderedHash.new
+          oh[:profile] = case level
+                         when :off
+                           0
+                         when :slow_only
+                           1
+                         when :all
+                           2
+                         else
+                           raise "Error: illegal profiling level value #{level}"
+                         end
+          doc = @db.db_command(oh)
+          raise "Error with profile command: #{doc.inspect}" unless @db.ok?(doc)
+        end
+
+        # Return an array contining current profiling information from the
+        # database.
+        def profiling_info
+        end
+
+        # Validate a named collection.
+        def validate_collection(name)
+        end
+
+      end
+    end
+  end
+end
diff --git a/lib/mongo/db.rb b/lib/mongo/db.rb
index 1287daa..3579787 100644
--- a/lib/mongo/db.rb
+++ b/lib/mongo/db.rb
@@ -21,6 +21,7 @@ require 'mongo/collection'
 require 'mongo/message'
 require 'mongo/query'
 require 'mongo/util/ordered_hash.rb'
+require 'mongo/admin'
 
 module XGen
   module Mongo
@@ -116,8 +117,6 @@ module XGen
         end
 
         def admin
-          # TODO
-          raise "not implemented"
           Admin.new(self)
         end
 
@@ -278,8 +277,6 @@ module XGen
           "#{@name}.#{collection_name}"
         end
 
-        protected
-
         # Return +true+ if +doc+ contains an 'ok' field with the value 1.
         def ok?(doc)
           ok = doc['ok']
@@ -289,6 +286,8 @@ module XGen
         # DB commands need to be ordered, so selector must be an OrderedHash
         # (or a Hash with only one element). What DB commands really need is
         # that the "command" key be first.
+        #
+        # Do not call this. Intended for driver use only.
         def db_command(selector)
           if !selector.kind_of?(OrderedHash)
             if !selector.kind_of?(Hash) || selector.keys.length > 1
diff --git a/tests/test_admin.rb b/tests/test_admin.rb
new file mode 100644
index 0000000..308e269
--- /dev/null
+++ b/tests/test_admin.rb
@@ -0,0 +1,40 @@
+$LOAD_PATH[0,0] = File.join(File.dirname(__FILE__), '..', 'lib')
+require 'mongo'
+require 'test/unit'
+
+# NOTE: assumes Mongo is running
+class AdminTest < Test::Unit::TestCase
+
+  include XGen::Mongo::Driver
+
+  def setup
+    host = ENV['MONGO_RUBY_DRIVER_HOST'] || 'localhost'
+    port = ENV['MONGO_RUBY_DRIVER_PORT'] || Mongo::DEFAULT_PORT
+    @db = Mongo.new(host, port).db('ruby-mongo-test')
+    # Insert some data to make sure the database itself exists.
+    @coll = @db.collection('test')
+    @coll.clear
+    @r1 = @coll.insert('a' => 1) # collection not created until it's used
+    @coll_full_name = 'ruby-mongo-test.test'
+    @admin = @db.admin
+  end
+
+  def teardown
+    unless @db.socket.closed?
+      @admin.profiling_level = :off
+      @coll.clear unless @coll == nil
+    end
+  end
+
+  def test_default_profiling_level
+    assert_equal :off, @admin.profiling_level
+  end
+
+  def test_change_profiling_level
+    @admin.profiling_level = :slow_only
+    assert_equal :slow_only, @admin.profiling_level
+    @admin.profiling_level = :off
+    assert_equal :off, @admin.profiling_level
+  end
+
+end