diff --git a/pyqtgraph/multiprocess/parallelizer.py b/pyqtgraph/multiprocess/parallelizer.py
index 86298023..ef00be7c 100644
--- a/pyqtgraph/multiprocess/parallelizer.py
+++ b/pyqtgraph/multiprocess/parallelizer.py
@@ -195,6 +195,8 @@ class Parallelize(object):
         finally:
             if self.showProgress:
                 self.progressDlg.__exit__(None, None, None)
+            for ch in self.childs:
+                ch.join()
         if len(self.exitCodes) < len(self.childs):
             raise Exception("Parallelizer started %d processes but only received exit codes from %d." % (len(self.childs), len(self.exitCodes)))
         for code in self.exitCodes:
diff --git a/pyqtgraph/multiprocess/processes.py b/pyqtgraph/multiprocess/processes.py
index 1be7e50b..0a372ef0 100644
--- a/pyqtgraph/multiprocess/processes.py
+++ b/pyqtgraph/multiprocess/processes.py
@@ -165,6 +165,7 @@ class Process(RemoteEventHandler):
                 if timeout is not None and time.time() - start > timeout:
                     raise Exception('Timed out waiting for remote process to end.')
                 time.sleep(0.05)
+        self.conn.close()
         self.debugMsg('Child process exited. (%d)' % self.proc.returncode)
 
     def debugMsg(self, msg, *args):
@@ -341,6 +342,7 @@ class ForkedProcess(RemoteEventHandler):
         except OSError:  ## probably remote process has already quit
             pass
         
+        self.conn.close()  # don't leak file handles!
         self.hasJoined = True
 
     def kill(self):