diff --git a/app/main.cpp b/app/main.cpp
--- a/app/main.cpp
+++ b/app/main.cpp
@@ -138,7 +138,17 @@
         if (command == "open") {
             QVector<UrlInfo> infos;
             stream >> infos;
+
+            QVector<UrlInfo> files, directories;
+            for(const auto &info: infos)
+                if (info.isDirectory())
+                    directories << info;
+                else
+                    files << info;
+
             openFiles(infos);
+            for(const auto &urlinfo: infos)
+                ICore::self()->projectController()->openProjectForUrl(urlinfo.url);
         } else {
             qCWarning(APP) << "Unknown remote command: " << command;
         }
@@ -198,7 +208,7 @@
         QDBusReply<bool> result = iface.call(QStringLiteral("openDocumentSimple"), file.url.toString(), file.cursor.line(), file.cursor.column());
         if ( ! result.value() ) {
             QTextStream err(stderr);
-            err << i18n("Could not open file %1.", file.url.toDisplayString(QUrl::PreferLocalFile)) << "\n";
+            err << i18n("Could not open file '%1'.", file.url.toDisplayString(QUrl::PreferLocalFile)) << "\n";
             errors_occured = true;
         }
     }
@@ -209,6 +219,29 @@
     return errors_occured;
 }
 
+/// Performs a DBus call to open the given @p files in the running kdev instance identified by @p pid
+/// Returns the exit status
+static int openProjectInRunningInstance(const QVector<UrlInfo>& paths, qint64 pid)
+{
+    const QString service = QStringLiteral("org.kdevelop.kdevelop-%1").arg(pid);
+    QDBusInterface iface(service, QStringLiteral("/org/kdevelop/ProjectController"), QStringLiteral("org.kdevelop.ProjectController"));
+    int errors = 0;
+
+    foreach ( const UrlInfo& path, paths ) {
+        QDBusReply<void> result = iface.call(QStringLiteral("openProjectForUrl"), path.url.toString());
+        if ( !result.isValid() ) {
+            QTextStream err(stderr);
+            err << i18n("Could not open project '%1': %2", path.url.toDisplayString(QUrl::PreferLocalFile), result.error().message()) << "\n";
+            ++errors;
+        }
+    }
+    // make the window visible
+    QDBusMessage makeVisible = QDBusMessage::createMethodCall( service, QStringLiteral("/kdevelop/MainWindow"), QStringLiteral("org.kdevelop.MainWindow"),
+                                                               QStringLiteral("ensureVisible") );
+    QDBusConnection::sessionBus().asyncCall( makeVisible );
+    return errors;
+}
+
 /// Gets the PID of a running KDevelop instance, eventually asking the user if there is more than one.
 /// Returns -1 in case there are no running sessions.
 static qint64 getRunningSessionPid()
@@ -470,16 +503,22 @@
 
     // Handle extra arguments, which stand for files to open
     QVector<UrlInfo> initialFiles;
+    QVector<UrlInfo> initialDirectories;
     foreach (const QString &file, parser.positionalArguments()) {
-        initialFiles.append(UrlInfo(file));
+        UrlInfo uinfo(file);
+        if (uinfo.isDirectory()) {
+            initialDirectories.append(uinfo);
+        } else {
+            initialFiles.append(uinfo);
+        }
     }
 
     const auto availableSessionInfos = KDevelop::SessionController::availableSessionInfos();
 
-    if (!initialFiles.isEmpty() && !parser.isSet(QStringLiteral("new-session"))) {
+    if ((!initialFiles.isEmpty() || !initialDirectories.isEmpty()) && !parser.isSet(QStringLiteral("new-session"))) {
 #if KDEVELOP_SINGLE_APP
         if (app.isRunning()) {
-            bool success = app.sendMessage(serializeOpenFilesMessage(initialFiles));
+            bool success = app.sendMessage(serializeOpenFilesMessage(initialFiles << initialDirectories));
             if (success) {
                 return 0;
             }
@@ -496,8 +535,9 @@
         } else {
             pid = getRunningSessionPid();
         }
+
         if ( pid > 0 ) {
-            return openFilesInRunningInstance(initialFiles, pid);
+            return openFilesInRunningInstance(initialFiles, pid) + openProjectInRunningInstance(initialDirectories, pid);
         }
         // else there are no running sessions, and the generated list of files will be opened below.
 #endif
@@ -729,6 +769,9 @@
         core->runControllerInternal()->execute(debugStr, launch);
     } else {
         openFiles(initialFiles);
+
+        for(const auto &urlinfo: initialDirectories)
+            core->projectController()->openProjectForUrl(urlinfo.url);
     }
 
 #if KDEVELOP_SINGLE_APP
diff --git a/app/urlinfo.h b/app/urlinfo.h
--- a/app/urlinfo.h
+++ b/app/urlinfo.h
@@ -86,6 +86,11 @@
         }
     }
 
+    bool isDirectory() const
+    {
+        return url.isLocalFile() && QDir(url.toLocalFile()).exists() && !cursor.isValid();
+    }
+
     /**
      * url computed out of the passed path
      */