diff --git a/testcases/complete-run.pl b/testcases/complete-run.pl
index 939ee636..a66b0982 100755
--- a/testcases/complete-run.pl
+++ b/testcases/complete-run.pl
@@ -50,10 +50,12 @@ sub slurp {
 }
 
 my $coverage_testing = 0;
+my $valgrind = 0;
 my @displays = ();
 
 my $result = GetOptions(
     "coverage-testing" => \$coverage_testing,
+    "valgrind" => \$valgrind,
     "display=s" => \@displays,
 );
 
@@ -143,6 +145,7 @@ sub take_job {
             configfile => $tmpfile,
             outdir => $outdir,
             logpath => $logpath,
+            valgrind => $valgrind,
             cv => $activate_cv
         );
 
@@ -190,7 +193,7 @@ sub take_job {
         my $output;
         open(my $spool, '>', \$output);
         my $parser = TAP::Parser->new({
-            exec => [ 'sh', '-c', qq|DISPLAY=$display LOGPATH="$logpath" OUTDIR="$outdir" /usr/bin/perl -Ilib $test| ],
+            exec => [ 'sh', '-c', qq|DISPLAY=$display LOGPATH="$logpath" OUTDIR="$outdir" VALGRIND=$valgrind /usr/bin/perl -Ilib $test| ],
             spool => $spool,
             merge => 1,
         });
diff --git a/testcases/lib/SocketActivation.pm b/testcases/lib/SocketActivation.pm
index 1ecfb2aa..4da2029c 100644
--- a/testcases/lib/SocketActivation.pm
+++ b/testcases/lib/SocketActivation.pm
@@ -78,6 +78,13 @@ sub activate_i3 {
         # the interactive signalhandler to make it crash immediately instead.
         my $i3cmd = abs_path("../i3") . " -V -d all --disable-signalhandler";
 
+        if ($args{valgrind}) {
+            $i3cmd =
+                qq|valgrind -v --log-file="$args{outdir}/valgrind.log" | .
+                qq|--leak-check=full --track-origins=yes --num-callers=20 | .
+                qq|--tool=memcheck -- $i3cmd|;
+        }
+
         # Append to $args{logpath} instead of overwriting because i3 might be
         # run multiple times in one testcase.
         my $cmd = "exec $i3cmd -c $args{configfile} >>$args{logpath} 2>&1";
diff --git a/testcases/lib/i3test.pm b/testcases/lib/i3test.pm
index 563837df..7473b617 100644
--- a/testcases/lib/i3test.pm
+++ b/testcases/lib/i3test.pm
@@ -435,6 +435,7 @@ sub launch_with_config {
         configfile => $tmpfile,
         outdir => $ENV{OUTDIR},
         logpath => $ENV{LOGPATH},
+        valgrind => $ENV{VALGRIND},
         cv => $cv,
     );