diff --git a/adapters.json b/adapters.json
index b9ec1b70cd2..bff61dd5cc9 100644
--- a/adapters.json
+++ b/adapters.json
@@ -1,4 +1,5 @@
 [
+    "a4g",
     "aardvark",
     "adblade",
     "adbund",
diff --git a/src/adapters/a4g.js b/src/adapters/a4g.js
new file mode 100644
index 00000000000..ee4afbde1ea
--- /dev/null
+++ b/src/adapters/a4g.js
@@ -0,0 +1,170 @@
+const bidfactory = require('../bidfactory.js'),
+  bidmanager = require('../bidmanager.js'),
+  constants = require('../constants.json'),
+  adloader = require('../adloader'),
+  utils = require('../utils.js');
+
+const A4G_BIDDER_CODE = 'a4g';
+const A4G_DEFAULT_BID_URL = '//ads.ad4game.com/v1/bid';
+
+const IFRAME_NESTING_PARAM_NAME = 'if';
+const LOCATION_PARAM_NAME = 'siteurl';
+const ID_PARAM_NAME = 'id';
+const ZONE_ID_PARAM_NAME = 'zoneId';
+const SIZE_PARAM_NAME = 'size';
+
+const A4G_SUPPORTED_PARAMS = [
+  IFRAME_NESTING_PARAM_NAME,
+  LOCATION_PARAM_NAME,
+  ID_PARAM_NAME,
+  ZONE_ID_PARAM_NAME,
+  SIZE_PARAM_NAME
+];
+
+const ARRAY_PARAM_SEPARATOR = ';';
+const ARRAY_SIZE_SEPARATOR = ',';
+const SIZE_SEPARATOR = 'x';
+
+const JSONP_PARAM_NAME = 'jsonp';
+
+function appendUrlParam(url, paramName, paramValue) {
+  const isQueryParams = url.indexOf('?') !== -1,
+    separator = isQueryParams ? '&' : '?';
+  return url + separator + encodeURIComponent(paramName) + '=' + encodeURIComponent(paramValue);
+}
+
+function isInIframe(windowObj) {
+  return windowObj !== windowObj.parent;
+}
+
+function getIframeInfo(window) {
+  let currentWindow = window,
+    iframeNestingLevel = 0,
+    hasExternalMeet = false,
+    hostHref = window.location.href;
+
+  while (isInIframe(currentWindow)) {
+    currentWindow = currentWindow.parent;
+
+    try {
+      if (hasExternalMeet) {
+        iframeNestingLevel = 1;
+      } else {
+        iframeNestingLevel++;
+      }
+
+      hostHref = currentWindow.document.referrer || currentWindow.location.href;
+    } catch (e) {
+      hasExternalMeet = true;
+    }
+  }
+
+  return {
+    nestingLevel: iframeNestingLevel,
+    hostHref: hostHref
+  };
+}
+
+function isValidStatus(status) {
+  return status === 200;
+}
+
+function bidParamsToQuery(params) {
+  return A4G_SUPPORTED_PARAMS
+    .reduce((url, paramName) => paramName in params
+      ? appendUrlParam(url, paramName, params[paramName])
+      : url,
+    '');
+}
+
+function buildBidRequestUrl(bidDeliveryUrl, params) {
+  return bidDeliveryUrl + bidParamsToQuery(params);
+}
+
+function createBidRequest(bidRequest) {
+  return (status) => bidfactory.createBid(status, bidRequest);
+}
+
+function mapBidToPrebidFormat(bidRequest, bid) {
+  const bidResponse = bidRequest(constants.STATUS.GOOD);
+
+  bidResponse.bidderCode = A4G_BIDDER_CODE;
+  bidResponse.cpm = bid.cpm;
+  bidResponse.ad = bid.ad;
+  bidResponse.width = bid.width;
+  bidResponse.height = bid.height;
+
+  return bidResponse;
+}
+
+function mapBidErrorToPrebid(bidRequest) {
+  return bidRequest(constants.STATUS.NO_BID);
+}
+
+function extractBidParams(bids) {
+  const idParams = [];
+  const sizeParams = [];
+  const zoneIds = [];
+
+  let deliveryUrl = '';
+
+  for (let i = 0; i < bids.length; i++) {
+    const bid = bids[i];
+    if (!deliveryUrl && typeof bid.params.deliveryUrl === 'string') {
+      deliveryUrl = bid.params.deliveryUrl;
+    }
+    idParams.push(bid.placementCode);
+    sizeParams.push(bid.sizes.map(size => size.join(SIZE_SEPARATOR)).join(ARRAY_SIZE_SEPARATOR));
+    zoneIds.push(bid.params.zoneId);
+  }
+
+  return [deliveryUrl, {
+    [ID_PARAM_NAME]: idParams.join(ARRAY_PARAM_SEPARATOR),
+    [ZONE_ID_PARAM_NAME]: zoneIds.join(ARRAY_PARAM_SEPARATOR),
+    [SIZE_PARAM_NAME]: sizeParams.join(ARRAY_PARAM_SEPARATOR)
+  }];
+}
+
+function a4gBidFactory() {
+
+  function generateJsonpCallbackName() {
+    return '__A4G' + Date.now();
+  }
+
+  function jsonp(url, callback) {
+    const callbackName = generateJsonpCallbackName(),
+          jsnopUrl = appendUrlParam(url, JSONP_PARAM_NAME, callbackName);
+
+    window[callbackName] = ({ status, response }) => {
+      !isValidStatus(status)
+        ? callback(new Error(`Failed fetching ad with status ${status}`), response)
+        : callback(null, response);
+      delete window[callbackName];
+    };
+
+    adloader.loadScript(jsnopUrl);
+  }
+
+  return {
+    callBids({ bids }) {
+      const bidRequests = bids.map(bid => createBidRequest(utils.getBidRequest(bid.bidId)));
+      const [ deliveryUrl, bidParams ] = extractBidParams(bids);
+      const { nestingLevel, hostHref } = getIframeInfo(window);
+      const envParams = { [IFRAME_NESTING_PARAM_NAME]: nestingLevel, [LOCATION_PARAM_NAME]: hostHref };
+      const bidsRequestUrl = buildBidRequestUrl(deliveryUrl || A4G_DEFAULT_BID_URL, Object.assign({}, bidParams, envParams));
+
+      jsonp(bidsRequestUrl, (error, bidsResponse) => {
+        for (let i = 0; i < bidRequests.length; i++) {
+          const bidRequest = bidRequests[i],
+            placementCode = bids[i].placementCode;
+
+            bidmanager.addBidResponse(placementCode,
+              error
+                ? mapBidErrorToPrebid(bidRequest)
+                : mapBidToPrebidFormat(bidRequest, bidsResponse[i]));
+        }});
+    }
+  };
+}
+
+module.exports = a4gBidFactory;
diff --git a/test/spec/adapters/a4g_spec.js b/test/spec/adapters/a4g_spec.js
new file mode 100644
index 00000000000..32a17d7a2ed
--- /dev/null
+++ b/test/spec/adapters/a4g_spec.js
@@ -0,0 +1,112 @@
+describe('a4g adapter tests', function () {
+  const expect = require('chai').expect;
+  const a4gBidFactory = require('src/adapters/a4g');
+  const bidmanager = require('src/bidmanager');
+  const adloader = require('src/adloader');
+  const constants = require('src/constants.json');
+
+  function readJsonpCallbackName(url) {
+    return /&jsonp=([_a-zA-Z0-9]+)/.exec(url)[1];
+  }
+
+  let spyLoadScript,
+    spyAddBidResponse,
+    a4gAdapter;
+
+  before(() => {
+    spyLoadScript = sinon.spy(adloader, 'loadScript');
+    spyAddBidResponse = sinon.spy(bidmanager, 'addBidResponse');
+  });
+
+  after(() => {
+    adloader.loadScript.restore();
+    bidmanager.addBidResponse.restore();
+  });
+
+  beforeEach(() => {
+    a4gAdapter = a4gBidFactory();
+  });
+
+  it('should send proper jsonp request to default deliveryUrl', () => {
+    a4gAdapter.callBids({ bids: [{
+      placementCode: 'pc1',
+      sizes: [[1, 2], [3, 4]],
+      params: {
+        zoneId: 1
+      }
+    }, {
+      placementCode: 'pc2',
+      sizes: [[5, 6]],
+      params: {
+        zoneId: 2
+      }
+    }]});
+
+    let targetUrl = spyLoadScript.lastCall.args[0];
+    expect(targetUrl).to.contain('ads.ad4game.com/v1/bid');
+    expect(targetUrl).to.contain('jsonp=');
+    expect(targetUrl).to.contain('id=pc1%3Bpc2');
+    expect(targetUrl).to.contain('size=1x2%2C3x4%3B5x6');
+    expect(targetUrl).to.contain('zoneId=1%3B2');
+  });
+
+  it('should send proper jsonp request to deliveryUrl from 1st bid', () => {
+    a4gAdapter.callBids({ bids: [{
+      placementCode: 'pc1',
+      sizes: [[1, 2], [3, 4]],
+      params: {
+        zoneId: 1,
+        deliveryUrl: 'new.test.delivery.com:8080/v105/new_bid'
+      }
+    }, {
+      placementCode: 'pc2',
+      sizes: [[5, 6]],
+      params: {
+        zoneId: 2,
+        deliveryUrl: 'nonused.test.delivery.com:8080/v105/new_bid'
+      }
+    }]});
+
+    let targetUrl = spyLoadScript.lastCall.args[0];
+    expect(targetUrl).to.contain('new.test.delivery.com:8080/v105/new_bid');
+  });
+
+  describe('on jsonp callback', () => {
+    let jsonpCallbackName;
+
+    beforeEach(() => {
+      a4gAdapter.callBids({ bids: [{
+        placementCode: 'pc1',
+        sizes: [[1, 2], [3, 4]],
+        params: {
+          zoneId: 1
+        }
+      }]});
+      jsonpCallbackName = readJsonpCallbackName(spyLoadScript.lastCall.args[0]);
+    });
+
+    it('should unregister', () => {
+      window[jsonpCallbackName]({status: 200, response: [{id: 'pc1', width: 1, height: 2, cpm: 1.0, ad: '' }]});
+      expect(window[jsonpCallbackName]).to.not.be.a('function');
+    });
+
+    it('should set all responses as bad if error received', () => {
+      window[jsonpCallbackName]({status: 400, response: []});
+      let [placementCode, bid] = spyAddBidResponse.lastCall.args;
+      expect(placementCode).to.equal('pc1');
+      expect(bid.getStatusCode()).to.equal(constants.STATUS.NO_BID);
+    });
+
+    it('should set all responses as good with appropriate values if ok', () => {
+      window[jsonpCallbackName]({status: 200, response: [{id: 'pc1', width: 1, height: 2, cpm: 1.0, ad: 'test' }]});
+      let [placementCode, bid] = spyAddBidResponse.lastCall.args;
+      expect(placementCode).to.equal('pc1');
+
+      expect(bid.getStatusCode()).to.equal(constants.STATUS.GOOD);
+      expect(bid.cpm).to.equal(1);
+      expect(bid.ad).to.equal('test');
+      expect(bid.width).to.equal(1);
+      expect(bid.height).to.equal(2);
+    });
+  });
+});