If it works when you slow things down with alerts, it looks like you may actually want an SJAX (!) call--I mean, if this page is pounding the browser with tons of AJAX threads, maybe you only want to do one at a time--Synchronously. so, instead of: $.getJSON("http://library.paulsmiths.edu/issnsearch/ispeerreviewed.php?i ssn=" + issn + "&jsoncallback=?",function(json, textStatus) { alert("test2"); allHTMLTags[i].innerHTML= "(" + issn + ") Peer Reviewed: " + json.peerreviewed; }); maybe something like: $.ajax({ type: "GET", async: false, url: "http://library.paulsmiths.edu/issnsearch/ispeerreviewed.php?issn=" + issn, dataType: "jsonp", success: function(json, textStatus) { alert("test2"); allHTMLTags[i].innerHTML= "(" + issn + ") Peer Reviewed: " + json.peerreviewed; } }); Also, I agree with what other folks said about using as much jQuery as possible. Jason