diff --git a/dist/pofile.js b/dist/pofile.js
index 0a73481..a31e945 100644
--- a/dist/pofile.js
+++ b/dist/pofile.js
@@ -1,4 +1,4 @@
-require=(function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
+require=(function(){function r(e,n,t){function o(i,f){if(!n[i]){if(!e[i]){var c="function"==typeof require&&require;if(!f&&c)return c(i,!0);if(u)return u(i,!0);var a=new Error("Cannot find module '"+i+"'");throw a.code="MODULE_NOT_FOUND",a}var p=n[i]={exports:{}};e[i][0].call(p.exports,function(r){var n=e[i][1][r];return o(n||r)},p,p.exports,r,e,n,t)}return n[i].exports}for(var u="function"==typeof require&&require,i=0;i<t.length;i++)o(t[i]);return o}return r})()({1:[function(require,module,exports){
 
 },{}],"pofile":[function(require,module,exports){
 var fs = require('fs');
@@ -11,6 +11,7 @@ var PO = function () {
     this.comments = [];
     this.extractedComments = [];
     this.headers = {};
+    this.headerOrder = [];
     this.items = [];
 };
 
@@ -35,9 +36,24 @@ PO.prototype.toString = function () {
     lines.push('msgid ""');
     lines.push('msgstr ""');
 
-    var keys = Object.keys(this.headers);
     var self = this;
+    var headerOrder = [];
+
+    this.headerOrder.forEach(function (key) {
+        if (key in self.headers) {
+            headerOrder.push(key);
+        }
+    });
+
+    var keys = Object.keys(this.headers);
+
     keys.forEach(function (key) {
+        if (headerOrder.indexOf(key) === -1) {
+            headerOrder.push(key);
+        }
+    });
+
+    headerOrder.forEach(function (key) {
         lines.push('"' + key + ': ' + self.headers[key] + '\\n"');
     });
 
@@ -91,6 +107,7 @@ PO.parse = function (data) {
         'Content-Transfer-Encoding': '',
         'Plural-Forms': '',
     };
+    po.headerOrder = [];
 
     headers.split(/\n/).reduce(function (acc, line) {
         if (acc.merge) {
@@ -114,6 +131,7 @@ PO.parse = function (data) {
             var name = p.shift().trim();
             var value = p.join(':').trim();
             po.headers[name] = value;
+            po.headerOrder.push(name);
         }
     });
 
diff --git a/dist/pofile.min.js b/dist/pofile.min.js
index 4400712..9b4beb1 100644
--- a/dist/pofile.min.js
+++ b/dist/pofile.min.js
@@ -1 +1 @@
-require=function a(b,c,d){function e(g,h){if(!c[g]){if(!b[g]){var i="function"==typeof require&&require;if(!h&&i)return i(g,!0);if(f)return f(g,!0);var j=new Error("Cannot find module '"+g+"'");throw j.code="MODULE_NOT_FOUND",j}var k=c[g]={exports:{}};b[g][0].call(k.exports,function(a){var c=b[g][1][a];return e(c?c:a)},k,k.exports,a,b,c,d)}return c[g].exports}for(var f="function"==typeof require&&require,g=0;g<d.length;g++)e(d[g]);return e}({1:[function(a,b,c){},{}],pofile:[function(a,b,c){function d(a){return a.replace(/^\s+|\s+$/g,"")}var e=a("fs"),f=function(){this.comments=[],this.extractedComments=[],this.headers={},this.items=[]};f.prototype.save=function(a,b){e.writeFile(a,this.toString(),b)},f.prototype.toString=function(){var a=[];this.comments&&this.comments.forEach(function(b){a.push(("# "+b).trim())}),this.extractedComments&&this.extractedComments.forEach(function(b){a.push(("#. "+b).trim())}),a.push('msgid ""'),a.push('msgstr ""');var b=Object.keys(this.headers),c=this;return b.forEach(function(b){a.push('"'+b+": "+c.headers[b]+'\\n"')}),a.push(""),this.items.forEach(function(b){a.push(b.toString()),a.push("")}),a.join("\n")},f.load=function(a,b){e.readFile(a,"utf-8",function(a,c){if(a)return b(a);var d=f.parse(c);b(null,d)})},f.parse=function(a){function b(){l.msgid.length>0&&(o>=p&&(l.obsolete=!0),o=0,p=0,e.items.push(l),l=new f.Item({nplurals:k}))}function c(a){return a=d(a),a=a.replace(/^[^"]*"|"$/g,""),a=a.replace(/\\([abtnvfr'"\\?]|([0-7]{3})|x([0-9a-fA-F]{2}))/g,function(a,b,c,d){if(c)return String.fromCharCode(parseInt(c,8));if(d)return String.fromCharCode(parseInt(d,16));switch(b){case"a":return"";case"b":return"\b";case"t":return"\t";case"n":return"\n";case"v":return"\v";case"f":return"\f";case"r":return"\r";default:return b}})}a=a.replace(/\r\n/g,"\n");for(var e=new f,g=a.split(/\n\n/),h=[];g[0]&&(0===h.length||h[h.length-1].indexOf('msgid ""')<0);)g[0].match(/msgid "[^"]/)?h.push('msgid ""'):h.push(g.shift());h=h.join("\n");var i=g.join("\n").split(/\n/);e.headers={"Project-Id-Version":"","Report-Msgid-Bugs-To":"","POT-Creation-Date":"","PO-Revision-Date":"","Last-Translator":"",Language:"","Language-Team":"","Content-Type":"","Content-Transfer-Encoding":"","Plural-Forms":""},h.split(/\n/).reduce(function(a,b){return a.merge&&(b=a.pop().slice(0,-1)+b.slice(1),delete a.merge),/^".*"$/.test(b)&&!/^".*\\n"$/.test(b)&&(a.merge=!0),a.push(b),a},[]).forEach(function(a){if(a.match(/^#\./))e.extractedComments.push(a.replace(/^#\.\s*/,""));else if(a.match(/^#/))e.comments.push(a.replace(/^#\s*/,""));else if(a.match(/^"/)){a=a.trim().replace(/^"/,"").replace(/\\n"$/,"");var b=a.split(/:/),c=b.shift().trim(),d=b.join(":").trim();e.headers[c]=d}});for(var j=f.parsePluralForms(e.headers["Plural-Forms"]),k=j.nplurals,l=new f.Item({nplurals:k}),m=null,n=0,o=0,p=0;i.length>0;){var q=d(i.shift()),r=!1;if(q.match(/^#\~/)&&(q=d(q.substring(2)),r=!0),q.match(/^#:/))b(),l.references.push(d(q.replace(/^#:/,"")));else if(q.match(/^#,/)){b();for(var s=d(q.replace(/^#,/,"")).split(","),t=0;t<s.length;t++)l.flags[s[t]]=!0}else if(q.match(/^#($|\s+)/))b(),l.comments.push(d(q.replace(/^#($|\s+)/,"")));else if(q.match(/^#\./))b(),l.extractedComments.push(d(q.replace(/^#\./,"")));else if(q.match(/^msgid_plural/))l.msgid_plural=c(q),m="msgid_plural",p++;else if(q.match(/^msgid/))b(),l.msgid=c(q),m="msgid",p++;else if(q.match(/^msgstr/)){var u=q.match(/^msgstr\[(\d+)\]/);n=u&&u[1]?parseInt(u[1]):0,l.msgstr[n]=c(q),m="msgstr",p++}else q.match(/^msgctxt/)?(b(),l.msgctxt=c(q),m="msgctxt",p++):q.length>0&&(p++,"msgstr"===m?l.msgstr[n]+=c(q):"msgid"===m?l.msgid+=c(q):"msgid_plural"===m?l.msgid_plural+=c(q):"msgctxt"===m&&(l.msgctxt+=c(q)));r&&o++}return b(),e},f.parsePluralForms=function(a){var b=(a||"").split(";").reduce(function(a,b){var c=b.trim(),d=c.indexOf("="),e=c.substring(0,d).trim(),f=c.substring(d+1).trim();return a[e]=f,a},{});return{nplurals:b.nplurals,plural:b.plural}},f.Item=function(a){var b=a&&a.nplurals;this.msgid="",this.msgctxt=null,this.references=[],this.msgid_plural=null,this.msgstr=[],this.comments=[],this.extractedComments=[],this.flags={},this.obsolete=!1;var c=Number(b);this.nplurals=isNaN(c)?2:c},f.Item.prototype.toString=function(){var a=[],b=this,c=function(a){return a=a.replace(/[\x07\b\t\v\f\r"\\]/g,function(a){switch(a){case"":return"\\a";case"\b":return"\\b";case"\t":return"\\t";case"\v":return"\\v";case"\f":return"\\f";case"\r":return"\\r";default:return"\\"+a}})},d=function(a,b,d){var e=[],f=b.split(/\n/),g="undefined"!=typeof d?"["+d+"]":"";return f.length>1?(e.push(a+g+' ""'),f.forEach(function(a){e.push('"'+c(a)+'"')})):e.push(a+g+' "'+c(b)+'"'),e},e=function(a,b,c){for(var e=d(a,b,c),f=1;f<e.length-1;f++)e[f]=e[f].slice(0,-1)+'\\n"';return e};this.comments.forEach(function(b){a.push("# "+b)}),this.extractedComments.forEach(function(b){a.push("#. "+b)}),this.references.forEach(function(b){a.push("#: "+b)});var f=Object.keys(this.flags).filter(function(a){return!!this.flags[a]},this);f.length>0&&a.push("#, "+f.join(","));var g=this.obsolete?"#~ ":"";return["msgctxt","msgid","msgid_plural","msgstr"].forEach(function(c){var f=b[c];if(null!=f){var h=!1;if(Array.isArray(f)&&(h=f.some(function(a){return a})),Array.isArray(f)&&f.length>1)f.forEach(function(b,d){var f=e(c,b,d);a=a.concat(g+f.join("\n"+g))});else if(b.msgid_plural&&"msgstr"===c&&!h)for(var i=0;i<b.nplurals;i++)a=a.concat(g+d(c,"",i));else{var j=b.msgid_plural&&Array.isArray(f)?0:void 0;f=Array.isArray(f)?f.join():f;var k=e(c,f,j);a=a.concat(g+k.join("\n"+g))}}}),a.join("\n")},b.exports=f},{fs:1}]},{},["pofile"]);
\ No newline at end of file
+require=function(){function a(b,c,d){function e(g,h){if(!c[g]){if(!b[g]){var i="function"==typeof require&&require;if(!h&&i)return i(g,!0);if(f)return f(g,!0);var j=new Error("Cannot find module '"+g+"'");throw j.code="MODULE_NOT_FOUND",j}var k=c[g]={exports:{}};b[g][0].call(k.exports,function(a){var c=b[g][1][a];return e(c||a)},k,k.exports,a,b,c,d)}return c[g].exports}for(var f="function"==typeof require&&require,g=0;g<d.length;g++)e(d[g]);return e}return a}()({1:[function(a,b,c){},{}],pofile:[function(a,b,c){function d(a){return a.replace(/^\s+|\s+$/g,"")}var e=a("fs"),f=function(){this.comments=[],this.extractedComments=[],this.headers={},this.headerOrder=[],this.items=[]};f.prototype.save=function(a,b){e.writeFile(a,this.toString(),b)},f.prototype.toString=function(){var a=[];this.comments&&this.comments.forEach(function(b){a.push(("# "+b).trim())}),this.extractedComments&&this.extractedComments.forEach(function(b){a.push(("#. "+b).trim())}),a.push('msgid ""'),a.push('msgstr ""');var b=this,c=[];this.headerOrder.forEach(function(a){a in b.headers&&c.push(a)});var d=Object.keys(this.headers);return d.forEach(function(a){c.indexOf(a)===-1&&c.push(a)}),c.forEach(function(c){a.push('"'+c+": "+b.headers[c]+'\\n"')}),a.push(""),this.items.forEach(function(b){a.push(b.toString()),a.push("")}),a.join("\n")},f.load=function(a,b){e.readFile(a,"utf-8",function(a,c){if(a)return b(a);var d=f.parse(c);b(null,d)})},f.parse=function(a){function b(){l.msgid.length>0&&(o>=p&&(l.obsolete=!0),o=0,p=0,e.items.push(l),l=new f.Item({nplurals:k}))}function c(a){return a=d(a),a=a.replace(/^[^"]*"|"$/g,""),a=a.replace(/\\([abtnvfr'"\\?]|([0-7]{3})|x([0-9a-fA-F]{2}))/g,function(a,b,c,d){if(c)return String.fromCharCode(parseInt(c,8));if(d)return String.fromCharCode(parseInt(d,16));switch(b){case"a":return"";case"b":return"\b";case"t":return"\t";case"n":return"\n";case"v":return"\v";case"f":return"\f";case"r":return"\r";default:return b}})}a=a.replace(/\r\n/g,"\n");for(var e=new f,g=a.split(/\n\n/),h=[];g[0]&&(0===h.length||h[h.length-1].indexOf('msgid ""')<0);)g[0].match(/msgid "[^"]/)?h.push('msgid ""'):h.push(g.shift());h=h.join("\n");var i=g.join("\n").split(/\n/);e.headers={"Project-Id-Version":"","Report-Msgid-Bugs-To":"","POT-Creation-Date":"","PO-Revision-Date":"","Last-Translator":"",Language:"","Language-Team":"","Content-Type":"","Content-Transfer-Encoding":"","Plural-Forms":""},e.headerOrder=[],h.split(/\n/).reduce(function(a,b){return a.merge&&(b=a.pop().slice(0,-1)+b.slice(1),delete a.merge),/^".*"$/.test(b)&&!/^".*\\n"$/.test(b)&&(a.merge=!0),a.push(b),a},[]).forEach(function(a){if(a.match(/^#\./))e.extractedComments.push(a.replace(/^#\.\s*/,""));else if(a.match(/^#/))e.comments.push(a.replace(/^#\s*/,""));else if(a.match(/^"/)){a=a.trim().replace(/^"/,"").replace(/\\n"$/,"");var b=a.split(/:/),c=b.shift().trim(),d=b.join(":").trim();e.headers[c]=d,e.headerOrder.push(c)}});for(var j=f.parsePluralForms(e.headers["Plural-Forms"]),k=j.nplurals,l=new f.Item({nplurals:k}),m=null,n=0,o=0,p=0;i.length>0;){var q=d(i.shift()),r=!1;if(q.match(/^#\~/)&&(q=d(q.substring(2)),r=!0),q.match(/^#:/))b(),l.references.push(d(q.replace(/^#:/,"")));else if(q.match(/^#,/)){b();for(var s=d(q.replace(/^#,/,"")).split(","),t=0;t<s.length;t++)l.flags[s[t]]=!0}else if(q.match(/^#($|\s+)/))b(),l.comments.push(d(q.replace(/^#($|\s+)/,"")));else if(q.match(/^#\./))b(),l.extractedComments.push(d(q.replace(/^#\./,"")));else if(q.match(/^msgid_plural/))l.msgid_plural=c(q),m="msgid_plural",p++;else if(q.match(/^msgid/))b(),l.msgid=c(q),m="msgid",p++;else if(q.match(/^msgstr/)){var u=q.match(/^msgstr\[(\d+)\]/);n=u&&u[1]?parseInt(u[1]):0,l.msgstr[n]=c(q),m="msgstr",p++}else q.match(/^msgctxt/)?(b(),l.msgctxt=c(q),m="msgctxt",p++):q.length>0&&(p++,"msgstr"===m?l.msgstr[n]+=c(q):"msgid"===m?l.msgid+=c(q):"msgid_plural"===m?l.msgid_plural+=c(q):"msgctxt"===m&&(l.msgctxt+=c(q)));r&&o++}return b(),e},f.parsePluralForms=function(a){var b=(a||"").split(";").reduce(function(a,b){var c=b.trim(),d=c.indexOf("="),e=c.substring(0,d).trim(),f=c.substring(d+1).trim();return a[e]=f,a},{});return{nplurals:b.nplurals,plural:b.plural}},f.Item=function(a){var b=a&&a.nplurals;this.msgid="",this.msgctxt=null,this.references=[],this.msgid_plural=null,this.msgstr=[],this.comments=[],this.extractedComments=[],this.flags={},this.obsolete=!1;var c=Number(b);this.nplurals=isNaN(c)?2:c},f.Item.prototype.toString=function(){var a=[],b=this,c=function(a){return a=a.replace(/[\x07\b\t\v\f\r"\\]/g,function(a){switch(a){case"":return"\\a";case"\b":return"\\b";case"\t":return"\\t";case"\v":return"\\v";case"\f":return"\\f";case"\r":return"\\r";default:return"\\"+a}})},d=function(a,b,d){var e=[],f=b.split(/\n/),g="undefined"!=typeof d?"["+d+"]":"";return f.length>1?(e.push(a+g+' ""'),f.forEach(function(a){e.push('"'+c(a)+'"')})):e.push(a+g+' "'+c(b)+'"'),e},e=function(a,b,c){for(var e=d(a,b,c),f=1;f<e.length-1;f++)e[f]=e[f].slice(0,-1)+'\\n"';return e};this.comments.forEach(function(b){a.push("# "+b)}),this.extractedComments.forEach(function(b){a.push("#. "+b)}),this.references.forEach(function(b){a.push("#: "+b)});var f=Object.keys(this.flags).filter(function(a){return!!this.flags[a]},this);f.length>0&&a.push("#, "+f.join(","));var g=this.obsolete?"#~ ":"";return["msgctxt","msgid","msgid_plural","msgstr"].forEach(function(c){var f=b[c];if(null!=f){var h=!1;if(Array.isArray(f)&&(h=f.some(function(a){return a})),Array.isArray(f)&&f.length>1)f.forEach(function(b,d){var f=e(c,b,d);a=a.concat(g+f.join("\n"+g))});else if(b.msgid_plural&&"msgstr"===c&&!h)for(var i=0;i<b.nplurals;i++)a=a.concat(g+d(c,"",i));else{var j=b.msgid_plural&&Array.isArray(f)?0:void 0;f=Array.isArray(f)?f.join():f;var k=e(c,f,j);a=a.concat(g+k.join("\n"+g))}}}),a.join("\n")},b.exports=f},{fs:1}]},{},["pofile"]);
\ No newline at end of file
diff --git a/lib/po.js b/lib/po.js
index 299f9f8..a0934a6 100644
--- a/lib/po.js
+++ b/lib/po.js
@@ -8,6 +8,7 @@ var PO = function () {
     this.comments = [];
     this.extractedComments = [];
     this.headers = {};
+    this.headerOrder = [];
     this.items = [];
 };
 
@@ -32,9 +33,24 @@ PO.prototype.toString = function () {
     lines.push('msgid ""');
     lines.push('msgstr ""');
 
-    var keys = Object.keys(this.headers);
     var self = this;
+    var headerOrder = [];
+
+    this.headerOrder.forEach(function (key) {
+        if (key in self.headers) {
+            headerOrder.push(key);
+        }
+    });
+
+    var keys = Object.keys(this.headers);
+
     keys.forEach(function (key) {
+        if (headerOrder.indexOf(key) === -1) {
+            headerOrder.push(key);
+        }
+    });
+
+    headerOrder.forEach(function (key) {
         lines.push('"' + key + ': ' + self.headers[key] + '\\n"');
     });
 
@@ -88,6 +104,7 @@ PO.parse = function (data) {
         'Content-Transfer-Encoding': '',
         'Plural-Forms': '',
     };
+    po.headerOrder = [];
 
     headers.split(/\n/).reduce(function (acc, line) {
         if (acc.merge) {
@@ -111,6 +128,7 @@ PO.parse = function (data) {
             var name = p.shift().trim();
             var value = p.join(':').trim();
             po.headers[name] = value;
+            po.headerOrder.push(name);
         }
     });
 
diff --git a/test/write.js b/test/write.js
index 9304f49..7e50320 100644
--- a/test/write.js
+++ b/test/write.js
@@ -504,4 +504,26 @@ describe('Write', function () {
             assert.ok(po.toString().indexOf('msgctxt') >= 0);
         });
     });
+
+    it('should keep the header order', function () {
+        var input = fs.readFileSync(__dirname + '/fixtures/big.po', 'utf8');
+        var po = PO.parse(input);
+        var str = po.toString();
+
+        assertHasContiguousLines(str, [
+            'msgid ""',
+            'msgstr ""',
+            '"Project-Id-Version: Link (6.x-2.9)\\n"',
+            '"POT-Creation-Date: 2011-12-31 23:39+0000\\n"',
+            '"PO-Revision-Date: 2013-12-17 14:21+0100\\n"',
+            '"Language-Team: French\\n"',
+            '"MIME-Version: 1.0\\n"',
+            '"Content-Type: text/plain; charset=UTF-8\\n"',
+            '"Content-Transfer-Encoding: 8bit\\n"',
+            '"Plural-Forms: nplurals=2; plural=(n > 1);\\n"',
+            '"Last-Translator: Ruben Vermeersch <ruben@rocketeer.be>\\n"',
+            '"Language: fr\\n"',
+            '"X-Generator: Poedit 1.6.2\\n"',
+        ]);
+    });
 });