diff --git a/doomsday/libdeng2/include/de/core/log.h b/doomsday/libdeng2/include/de/core/log.h
index 7c765dfa8b..747404d079 100644
--- a/doomsday/libdeng2/include/de/core/log.h
+++ b/doomsday/libdeng2/include/de/core/log.h
@@ -270,7 +270,7 @@ class DENG2_PUBLIC Log
  *
  * @ingroup core
  */
-class DENG2_PUBLIC LogEntry
+class DENG2_PUBLIC LogEntry : public Lockable
 {
 public:
     /**
@@ -434,7 +434,9 @@ class DENG2_PUBLIC LogEntry
     template <typename ValueType>
     inline LogEntry &operator << (ValueType const &v) {
         if(!_disabled) {
+            lock();
             _args.push_back(new Arg(v));
+            unlock();
         }
         return *this;
     }
diff --git a/doomsday/libdeng2/src/core/log.cpp b/doomsday/libdeng2/src/core/log.cpp
index fcca5f5cd4..5b59ccd727 100644
--- a/doomsday/libdeng2/src/core/log.cpp
+++ b/doomsday/libdeng2/src/core/log.cpp
@@ -21,6 +21,7 @@
 #include "de/Time"
 #include "de/Date"
 #include "de/LogBuffer"
+#include "de/Guard"
 #include "logtextstyle.h"
 
 #include <QMap>
@@ -76,6 +77,8 @@ LogEntry::LogEntry(Log::LogLevel level, String const &section, int sectionDepth,
 
 LogEntry::~LogEntry()
 {
+    DENG2_GUARD(this); // cannot delete if someone has a lock
+
     for(Args::iterator i = _args.begin(); i != _args.end(); ++i) 
     {
         delete *i;
@@ -84,6 +87,8 @@ LogEntry::~LogEntry()
 
 String LogEntry::asText(Flags const &formattingFlags, int shortenSection) const
 {
+    DENG2_GUARD(this); // others shouldn't touch the entry while we're converting
+
     /// @todo This functionality belongs in an entry formatter class.
 
     Flags flags = formattingFlags;