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    <p>The goal with node is not to care what order things happen in. This can complicate some scenarios. There is no shame in nesting callbacks. Once you are used to how it looks, you may find that you actually prefer that style. I do; it is very clear what order callbacks will fire. You can forgo the anonymous functions to make it less verbose if you have to.</p> <p>If you are willing to restructure your code a bit, you can use the "typical" nested callback method. If you want to avoid callbacks, there are numerous async frameworks that will try and help you do this. One that you might want to check out is async.js (https://github.com/fjakobs/async.js). Example of each:</p> <pre><code>app.get('/home', function (req,res) { var lock = 2; var result = {}; result.user_array = []; result.title_array = []; var finishRequest = function(result) { req.session.title_array = result.title_array; req.session.user_array = result.user_array; res.render('home.ejs', {layout: false, locals: { user_name: result.user_array, title: result.title_array }}); }; // first query var q1 = function(fn) { var sql = 'select user_name from users'; db.execute(sql) .addListener('row', function(r) { result.user_array.push( { user_name: r.user_name } ); }) .addListener('result', function(r) { return fn &amp;&amp; fn(null, result); }); }; // second query var q2 = function(fn) { var sql = 'select title from code_samples'; db.execute(sql) .addListener('row', function(r) { result.title_array.push( { title: r.title } ); }) .addListener('result', function(r) { return fn &amp;&amp; fn(null, result); }); } //Standard nested callbacks q1(function (err, result) { if (err) { return; //do something} q2(function (err, result) { if (err) { return; //do something} finishRequest(result); }); }); //Using async.js async.list([ q1, q2, ]).call().end(function(err, result) { finishRequest(result); }); }); </code></pre> <p>For a one-off, I would probably just use a reference counting type approach. Simply keep track of how many queries you want to execute and render the response when they have all finished.</p> <pre><code>app.get('/home', function (req,res) { var lock = 2; var user_array = []; var title_array = []; var finishRequest = function() { res.render('home.ejs', {layout: false, locals: { user_name: user_array, title: title_array }}); } // first query var sql = 'select user_name from users'; db.execute(sql) .addListener('row', function(r) { user_array.push( { user_name: r.user_name } ); }) .addListener('result', function(r) { req.session.user_array = user_array; lock -= 1; if (lock === 0) { finishRequest(); } }); // second query var sql = 'select title from code_samples'; db.execute(sql) .addListener('row', function(r) { title_array.push( { title: r.title } ); }) .addListener('result', function(r) { req.session.title_array = title_array; lock -= 1; if (lock === 0) { finishRequest(); } }); }); </code></pre> <p>An even nicer approach would be to simply call finishRequest() in each 'result' callback an check for non-empty arrays before you render the response. Whether that will work in your case depends on your requirements.</p>
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    1. COI always assumed that reference counting like this was a "hack" but it seems valid when callbacks are involved. Thanks for the example.
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    2. COIt is a bit hacky and I would certainly invest in a more robust method if I was going to be writing that all over my code. If you are willing to restructure a bit, you can avoid that. I updated my answer with more examples.
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    3. COThanks for the second example with async.js It's definitely a cleaner pattern. Thanks!
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