diff --git a/package.json b/package.json
index 14b877a54..cb0e381dd 100644
--- a/package.json
+++ b/package.json
@@ -167,6 +167,11 @@
                         "default": false,
                         "description": "Run namespace tests when opening a new file and on file save"
                     },
+                    "calva.outputStackTraceOnTest": {
+                      "type": "boolean",
+                      "default": false,
+                      "description": "Prints exception stacktraces in the test runner output"
+                    },
                     "calva.syncReplNamespaceToCurrentFile": {
                         "type": "boolean",
                         "default": false,
diff --git a/src/nrepl/index.ts b/src/nrepl/index.ts
index 702b8b457..86b257033 100644
--- a/src/nrepl/index.ts
+++ b/src/nrepl/index.ts
@@ -359,6 +359,19 @@ export class NReplSession {
         })
     }
 
+    testStacktrace(ns: string, test: string, index: number) {
+      return new Promise<any>((resolve, reject) => {
+          let id = this.client.nextId;
+          this.messageHandlers[id] = (msg) => {
+              resolve(msg);
+              return true;
+          }
+          this.client.write({
+            op: "test-stacktrace", id, session: this.sessionId, ns, "var": test, "index": index
+          });
+      });
+    }
+
     testNs(ns: string) {
         return new Promise<any>((resolve, reject) => {
             let id = this.client.nextId;
@@ -762,4 +775,4 @@ export class NReplEvaluation {
         });
         return (num);
     }
-}
\ No newline at end of file
+}
diff --git a/src/state.ts b/src/state.ts
index 8d03b73aa..fb914a3e2 100644
--- a/src/state.ts
+++ b/src/state.ts
@@ -102,6 +102,7 @@ function config() {
         format: configOptions.get("formatOnSave"),
         evaluate: configOptions.get("evalOnSave"),
         test: configOptions.get("testOnSave"),
+        outputStackTraceOnTest: configOptions.get("outputStackTraceOnTest") as boolean,
         syncReplNamespaceToCurrentFile: configOptions.get("syncReplNamespaceToCurrentFile"),
         jackInEnv: configOptions.get("jackInEnv"),
         openBrowserWhenFigwheelStarted: configOptions.get("openBrowserWhenFigwheelStarted") as boolean,
diff --git a/src/testRunner.ts b/src/testRunner.ts
index 3ff8e8009..a9521f74d 100644
--- a/src/testRunner.ts
+++ b/src/testRunner.ts
@@ -7,7 +7,7 @@ import { disabledPrettyPrinter } from './printer';
 
 let diagnosticCollection = vscode.languages.createDiagnosticCollection('calva');
 
-function reportTests(results, errorStr, log = true) {
+async function reportTests(results, errorStr, client, log = true) {
     let chan = state.outputChannel(),
         diagnostics = {},
         total_summary: { test, error, ns, var, fail } = { test: 0, error: 0, ns: 0, var: 0, fail: 0 };
@@ -31,8 +31,13 @@ function reportTests(results, errorStr, log = true) {
                             msg.push(resultItem.message);
                           return `${msg.join(": ")}${(msg.length > 0 ? "\n" : "")}`;
                         }
-                        if (a.type == "error" && log)
-                          chan.appendLine(`ERROR in ${ns}/${test} (line ${a.line}):\n${resultMessage(a)}   error: ${a.error} (${a.file})\nexpected: ${a.expected}`);
+                        if (a.type == "error" && log) {
+                          chan.appendLine(`ERROR in ${ns}/${test} (line ${a.line}):\n${resultMessage(a)}expected: ${a.expected}   error: ${a.error} (${a.file})`);
+                          if(state.config().outputStackTraceOnTest) {
+                            const exception = await client.testStacktrace(ns, test, a.index);
+                            chan.appendLine(formatException(exception));
+                          }
+                        }
                         if (a.type == "fail") {
                             let msg = `failure in test: ${test} context: ${a.context}, expected ${a.expected}, got: ${a.actual}`,
                                 err = new vscode.Diagnostic(new vscode.Range(a.line - 1, 0, a.line - 1, 1000), msg, vscode.DiagnosticSeverity.Error);
@@ -82,11 +87,26 @@ function reportTests(results, errorStr, log = true) {
     }
 }
 
+function formatException(ex) {
+  const basePad = 10;
+  const padStart = (s, n) => {
+    const l = s.toString().length;
+    return `${" ".repeat(n - l)}${s}`;
+  }
+  const maxLine = Math.max(...ex.stacktrace.map(s => s.line.toString().length));
+  const fileLine = (s) => `${s.file}:${padStart(s.line, maxLine)}`;
+  const maxPad = Math.max(...ex.stacktrace.map(s => fileLine(s).length));
+  return ex
+    .stacktrace
+    .map(s => `${padStart(fileLine(s), maxPad + basePad)} ${s.name}`)
+    .join("\n");
+}
+
 // FIXME: use cljs session where necessary
 async function runAllTests(document = {}) {
     let client = util.getSession(util.getFileType(document));
     state.outputChannel().appendLine("Running all project tests…");
-    reportTests([await client.testAll()], "Running all tests");
+    await reportTests([await client.testAll()], "Running all tests", client);
 }
 
 function runAllTestsCommand() {
@@ -121,7 +141,7 @@ function runNamespaceTests(document = {}) {
         if (nss.length > 1)
             resultPromises.push(client.testNs(nss[1]));
         let results = await Promise.all(resultPromises);
-        reportTests(results, "Running tests");
+        await reportTests(results, "Running tests", client);
     }, disabledPrettyPrinter).catch(() => {});
 }
 
@@ -134,7 +154,7 @@ async function runTestUnderCursor() {
     evaluate.loadFile(doc, async () => {
         state.outputChannel().appendLine(`Running test: ${test}…`);
         const results = [await client.test(ns, [test])];
-        reportTests(results, `Running test: ${test}`);
+        await reportTests(results, `Running test: ${test}`, client);
     }, disabledPrettyPrinter).catch(() => {});
 }
 
@@ -152,7 +172,7 @@ function rerunTests(document = {}) {
     let client = util.getSession(util.getFileType(document))
     evaluate.loadFile({}, async () => {
         state.outputChannel().appendLine("Running previously failed tests…");
-        reportTests([await client.retest()], "Retesting");
+        reportTests([await client.retest()], "Retesting", client);
     }, disabledPrettyPrinter).catch(() => {});
 }