diff --git a/.gitignore b/.gitignore
index 37ef81a..ccfff1d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -22,3 +22,4 @@ test/tmp
 test/version_tmp
 tmp
 tmtags
+.ruby-version
diff --git a/README.md b/README.md
index c1746bb..9be47e5 100644
--- a/README.md
+++ b/README.md
@@ -129,12 +129,18 @@ index = XmlSitemap::Index.new
 # or if you want the URLs to use HTTPS
 index = XmlSitemap::Index.new(:secure => true)
 
+# or gzip compression for all sitemaps
+index = XmlSitemap::Index.new(:gzip => true)
+
 # or via shortcut
 index = XmlSitemap.index
 
 # Add a map to the index
 index.add(map)
 
+# With a gzip option for current map
+index.add(map, :gzip => true)
+
 # Render as XML
 index.render
 
diff --git a/lib/xml-sitemap/index.rb b/lib/xml-sitemap/index.rb
index 7c486a3..e9858cd 100644
--- a/lib/xml-sitemap/index.rb
+++ b/lib/xml-sitemap/index.rb
@@ -1,36 +1,42 @@
 module XmlSitemap
   class Index
     attr_reader :maps
-    
+
     # Initialize a new Index instance
     #
     # opts   - Index options
     #
     # opts[:secure] - Force HTTPS for all items. (default: false)
+    # opts[:gzip] - Force .gzip extension for all items. (default: false)
     #
     def initialize(opts={})
-      @maps     = []
-      @offsets  = Hash.new(0)
-      @secure   = opts[:secure] || false
-      
+      @maps        = []
+      @offsets     = Hash.new(0)
+      @secure      = opts[:secure] || false
+      @global_gzip = opts[:gzip] || false
+
       yield self if block_given?
     end
-    
+
     # Add map object to index
     #
     # map - XmlSitemap::Map instance
     #
-    def add(map, use_offsets=true)
+    #def add(map, use_offsets=true)
+    def add(map, opts={})
       raise ArgumentError, 'XmlSitemap::Map object required!' unless map.kind_of?(XmlSitemap::Map)
       raise ArgumentError, 'Map is empty!' if map.empty?
-      
+
+      @local_gzip  = opts[:gzip] || false
+      @use_offsets = !opts[:use_offsets].nil? ? opts[:use_offsets] : true
+
       @maps << {
-        :loc     => use_offsets ? map.index_url(@offsets[map.group], @secure) : map.plain_index_url(@secure),
+        :loc     => set_map_loc(map),
         :lastmod => map.created_at.utc.iso8601
       }
       @offsets[map.group] += 1
     end
-    
+
     # Generate sitemap XML index
     #
     def render
@@ -45,7 +51,7 @@ def render
         end
       }.to_s
     end
-    
+
     # Render XML sitemap index into the file
     #
     # path    - Output filename
@@ -56,12 +62,28 @@ def render
     def render_to(path, options={})
       overwrite = options[:overwrite] || true
       path = File.expand_path(path)
-      
+
       if File.exists?(path) && !overwrite
         raise RuntimeError, "File already exists and not overwritable!"
       end
-      
+
       File.open(path, 'w') { |f| f.write(self.render) }
     end
+
+    private
+
+    # Set location for selected map
+    #
+    # map - XmlSitemap::Map instance
+    def set_map_loc(map)
+      loc = if @use_offsets
+        map.index_url(@offsets[map.group], @secure)
+      else
+        map.plain_index_url(@secure)
+      end
+
+      loc += '.gz' if @global_gzip || @local_gzip
+      loc
+    end
   end
 end
diff --git a/spec/fixtures/sample_index_with_gz.xml b/spec/fixtures/sample_index_with_gz.xml
new file mode 100644
index 0000000..c6a0d5e
--- /dev/null
+++ b/spec/fixtures/sample_index_with_gz.xml
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<sitemapindex xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9 http://www.sitemaps.org/schemas/sitemap/0.9/siteindex.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
+  <sitemap>
+    <loc>http://foobar.com/sitemap-0.xml.gz</loc>
+    <lastmod>2011-06-01T00:00:01Z</lastmod>
+  </sitemap>
+  <sitemap>
+    <loc>http://foobar.com/sitemap-1.xml.gz</loc>
+    <lastmod>2011-06-01T00:00:01Z</lastmod>
+  </sitemap>
+</sitemapindex>
diff --git a/spec/index_spec.rb b/spec/index_spec.rb
index 90b173c..00b7eec 100644
--- a/spec/index_spec.rb
+++ b/spec/index_spec.rb
@@ -51,8 +51,8 @@
       m2 = XmlSitemap::Map.new('two.foobar.com', :time => base_time) { |m| m.add('about') }
 
       index = XmlSitemap::Index.new do |i|
-        i.add(m1, false)
-        i.add(m2, false)
+        i.add(m1, :use_offsets => false)
+        i.add(m2, :use_offsets => false)
       end
 
       index.render.split("\n")[2..-1].join("\n").should == fixture('sample_many_subdomains_index.xml').split("\n")[2..-1].join("\n")
@@ -91,5 +91,31 @@
       index.render_to(index_path)
       File.read(index_path).split("\n")[2..-1].join("\n").should eq(fixture('group_index.xml').split("\n")[2..-1].join("\n"))
     end
+
+    it 'saves index contents to the filesystem with local gzip options for each map' do
+      m1 = XmlSitemap::Map.new('foobar.com', :time => base_time) { |m| m.add('about') }
+      m2 = XmlSitemap::Map.new('foobar.com', :time => base_time) { |m| m.add('about') }
+
+      index = XmlSitemap::Index.new do |i|
+        i.add(m1, :gzip => true)
+        i.add(m2, :gzip => true)
+      end
+
+      index.render_to(index_path)
+      File.read(index_path).split("\n")[2..-1].join("\n").should eq(fixture('sample_index_with_gz.xml').split("\n")[2..-1].join("\n"))
+    end
+
+    it 'saves index contents to the filesystem with global gzip options for all maps' do
+      m1 = XmlSitemap::Map.new('foobar.com', :time => base_time) { |m| m.add('about') }
+      m2 = XmlSitemap::Map.new('foobar.com', :time => base_time) { |m| m.add('about') }
+
+      index = XmlSitemap::Index.new(:gzip => true) do |i|
+        i.add(m1)
+        i.add(m2)
+      end
+
+      index.render_to(index_path)
+      File.read(index_path).split("\n")[2..-1].join("\n").should eq(fixture('sample_index_with_gz.xml').split("\n")[2..-1].join("\n"))
+    end
   end
 end