diff --git a/src/Cmd.cpp b/src/Cmd.cpp
index ec3761530..63f019c14 100644
--- a/src/Cmd.cpp
+++ b/src/Cmd.cpp
@@ -106,6 +106,8 @@ void Cmd::load ()
 {
   if (commands.size () == 0)
   {
+    commands.push_back ("_projects");
+    commands.push_back ("_tags");
     commands.push_back (context.stringtable.get (CMD_ADD,       "add"));
     commands.push_back (context.stringtable.get (CMD_APPEND,    "append"));
     commands.push_back (context.stringtable.get (CMD_ANNOTATE,  "annotate"));
@@ -182,7 +184,9 @@ void Cmd::allCustomReports (std::vector <std::string>& all) const
 // Commands that do not directly modify the data files.
 bool Cmd::isReadOnlyCommand ()
 {
-  if (command == context.stringtable.get (CMD_CALENDAR,  "calendar")  ||
+  if (command == "_projects"                                          ||
+      command == "_tags"                                              ||
+      command == context.stringtable.get (CMD_CALENDAR,  "calendar")  ||
       command == context.stringtable.get (CMD_COLORS,    "colors")    ||
       command == context.stringtable.get (CMD_EXPORT,    "export")    ||
       command == context.stringtable.get (CMD_HELP,      "help")      ||
diff --git a/src/Context.cpp b/src/Context.cpp
index ae98d23c0..d5ccc21af 100644
--- a/src/Context.cpp
+++ b/src/Context.cpp
@@ -169,35 +169,37 @@ std::string Context::dispatch ()
 
   // TODO Just look at this thing.  It cries out for a dispatch table.
   std::string out;
-       if (cmd.command == "projects")      { out = handleProjects        (); }
-  else if (cmd.command == "tags")          { out = handleTags            (); }
-  else if (cmd.command == "colors")        { out = handleColor           (); }
-  else if (cmd.command == "version")       { out = handleVersion         (); }
-  else if (cmd.command == "help")          { out = longUsage             (); }
-  else if (cmd.command == "stats")         { out = handleReportStats     (); }
-  else if (cmd.command == "info")          { out = handleInfo            (); }
-  else if (cmd.command == "history")       { out = handleReportHistory   (); }
-  else if (cmd.command == "ghistory")      { out = handleReportGHistory  (); }
-  else if (cmd.command == "summary")       { out = handleReportSummary   (); }
-  else if (cmd.command == "calendar")      { out = handleReportCalendar  (); }
-  else if (cmd.command == "timesheet")     { out = handleReportTimesheet (); }
-  else if (cmd.command == "add")           { out = handleAdd             (); }
-  else if (cmd.command == "append")        { out = handleAppend          (); }
-  else if (cmd.command == "annotate")      { out = handleAnnotate        (); }
-  else if (cmd.command == "done")          { out = handleDone            (); }
-  else if (cmd.command == "delete")        { out = handleDelete          (); }
-  else if (cmd.command == "start")         { out = handleStart           (); }
-  else if (cmd.command == "stop")          { out = handleStop            (); }
-  else if (cmd.command == "export")        { out = handleExport          (); }
-  else if (cmd.command == "import")        { out = handleImport          (); }
-  else if (cmd.command == "duplicate")     { out = handleDuplicate       (); }
-  else if (cmd.command == "edit")          { out = handleEdit            (); }
+       if (cmd.command == "projects")      { out = handleProjects           (); }
+  else if (cmd.command == "tags")          { out = handleTags               (); }
+  else if (cmd.command == "colors")        { out = handleColor              (); }
+  else if (cmd.command == "version")       { out = handleVersion            (); }
+  else if (cmd.command == "help")          { out = longUsage                (); }
+  else if (cmd.command == "stats")         { out = handleReportStats        (); }
+  else if (cmd.command == "info")          { out = handleInfo               (); }
+  else if (cmd.command == "history")       { out = handleReportHistory      (); }
+  else if (cmd.command == "ghistory")      { out = handleReportGHistory     (); }
+  else if (cmd.command == "summary")       { out = handleReportSummary      (); }
+  else if (cmd.command == "calendar")      { out = handleReportCalendar     (); }
+  else if (cmd.command == "timesheet")     { out = handleReportTimesheet    (); }
+  else if (cmd.command == "add")           { out = handleAdd                (); }
+  else if (cmd.command == "append")        { out = handleAppend             (); }
+  else if (cmd.command == "annotate")      { out = handleAnnotate           (); }
+  else if (cmd.command == "done")          { out = handleDone               (); }
+  else if (cmd.command == "delete")        { out = handleDelete             (); }
+  else if (cmd.command == "start")         { out = handleStart              (); }
+  else if (cmd.command == "stop")          { out = handleStop               (); }
+  else if (cmd.command == "export")        { out = handleExport             (); }
+  else if (cmd.command == "import")        { out = handleImport             (); }
+  else if (cmd.command == "duplicate")     { out = handleDuplicate          (); }
+  else if (cmd.command == "edit")          { out = handleEdit               (); }
 #ifdef FEATURE_SHELL
-  else if (cmd.command == "shell")         {       handleShell           (); }
+  else if (cmd.command == "shell")         {       handleShell              (); }
 #endif
-  else if (cmd.command == "undo")          {       handleUndo            (); }
+  else if (cmd.command == "undo")          {       handleUndo               (); }
+  else if (cmd.command == "_projects")     { out = handleCompletionProjects (); }
+  else if (cmd.command == "_tags")         { out = handleCompletionTags     (); }
   else if (cmd.command == "" &&
-           sequence.size ())               { out = handleModify          (); }
+           sequence.size ())               { out = handleModify             (); }
 
   // Command that display IDs and therefore need TDB::gc first.
   else if (cmd.command == "next")          { if (!inShadow) tdb.gc (); out = handleReportNext    (); }
diff --git a/src/command.cpp b/src/command.cpp
index bfb0dcc3f..d7682b26d 100644
--- a/src/command.cpp
+++ b/src/command.cpp
@@ -193,6 +193,31 @@ std::string handleProjects ()
   return out.str ();
 }
 
+////////////////////////////////////////////////////////////////////////////////
+std::string handleCompletionProjects ()
+{
+  std::vector <Task> tasks;
+  context.tdb.lock (context.config.get ("locking", true));
+  handleRecurrence ();
+  Filter filter;
+  context.tdb.loadPending (tasks, filter);
+  context.tdb.commit ();
+  context.tdb.unlock ();
+
+  // Scan all the tasks for their project name, building a map using project
+  // names as keys.
+  std::map <std::string, int> unique;
+  foreach (t, tasks)
+    unique[t->get ("project")] = 0;
+
+  std::stringstream out;
+  foreach (project, unique)
+    if (project->first.length ())
+      out << project->first << std::endl;
+
+  return out.str ();
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 std::string handleTags ()
 {
@@ -260,6 +285,36 @@ std::string handleTags ()
   return out.str ();
 }
 
+////////////////////////////////////////////////////////////////////////////////
+std::string handleCompletionTags ()
+{
+  std::vector <Task> tasks;
+  context.tdb.lock (context.config.get ("locking", true));
+  handleRecurrence ();
+  Filter filter;
+  context.tdb.loadPending (tasks, filter);
+  context.tdb.commit ();
+  context.tdb.unlock ();
+
+  // Scan all the tasks for their project name, building a map using project
+  // names as keys.
+  std::map <std::string, int> unique;
+  foreach (t, tasks)
+  {
+    std::vector <std::string> tags;
+    t->getTags (tags);
+
+    foreach (tag, tags)
+      unique[*tag] = 0;
+  }
+
+  std::stringstream out;
+  foreach (tag, unique)
+    out << tag->first << std::endl;
+
+  return out.str ();
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 void handleUndo ()
 {
diff --git a/src/main.h b/src/main.h
index 9a39ee35b..7993cae51 100644
--- a/src/main.h
+++ b/src/main.h
@@ -60,7 +60,9 @@ std::string handleExport ();
 std::string handleDone ();
 std::string handleModify ();
 std::string handleProjects ();
+std::string handleCompletionProjects ();
 std::string handleTags ();
+std::string handleCompletionTags ();
 std::string handleVersion ();
 std::string handleDelete ();
 std::string handleStart ();