diff --git a/src/io/file_manager.cpp b/src/io/file_manager.cpp
index 03de607a0..12e633f54 100644
--- a/src/io/file_manager.cpp
+++ b/src/io/file_manager.cpp
@@ -415,6 +415,7 @@ FileManager::~FileManager()
  */
 bool FileManager::fileExists(const std::string& path) const
 {
+    std::lock_guard<std::mutex> lock(m_file_system_lock);
 #ifdef DEBUG
     bool exists = m_file_system->existFile(path.c_str());
     if(exists) return true;
@@ -517,6 +518,8 @@ io::path FileManager::createAbsoluteFilename(const std::string &f)
  */
 void FileManager::pushModelSearchPath(const std::string& path)
 {
+    std::lock_guard<std::mutex> lock(m_file_system_lock);
+
     m_model_search_path.push_back(path);
     const int n=m_file_system->getFileArchiveCount();
     m_file_system->addFileArchive(createAbsoluteFilename(path),
@@ -544,6 +547,8 @@ void FileManager::pushModelSearchPath(const std::string& path)
  */
 void FileManager::pushTextureSearchPath(const std::string& path, const std::string& container_id)
 {
+    std::lock_guard<std::mutex> lock(m_file_system_lock);
+
     m_texture_search_path.push_back(TextureSearchPath(path, container_id));
     const int n=m_file_system->getFileArchiveCount();
     m_file_system->addFileArchive(createAbsoluteFilename(path),
@@ -571,8 +576,9 @@ void FileManager::pushTextureSearchPath(const std::string& path, const std::stri
  */
 void FileManager::popTextureSearchPath()
 {
-    if(!m_texture_search_path.empty())
+    if (!m_texture_search_path.empty())
     {
+        std::lock_guard<std::mutex> lock(m_file_system_lock);
         TextureSearchPath dir = m_texture_search_path.back();
         m_texture_search_path.pop_back();
         m_file_system->removeFileArchive(createAbsoluteFilename(dir.m_texture_search_path));
@@ -584,8 +590,9 @@ void FileManager::popTextureSearchPath()
  */
 void FileManager::popModelSearchPath()
 {
-    if(!m_model_search_path.empty())
+    if (!m_model_search_path.empty())
     {
+        std::lock_guard<std::mutex> lock(m_file_system_lock);
         std::string dir = m_model_search_path.back();
         m_model_search_path.pop_back();
         m_file_system->removeFileArchive(createAbsoluteFilename(dir));
diff --git a/src/io/file_manager.hpp b/src/io/file_manager.hpp
index 49a18291c..4aec7c4eb 100644
--- a/src/io/file_manager.hpp
+++ b/src/io/file_manager.hpp
@@ -25,6 +25,7 @@
  * Contains generic utility classes for file I/O (especially XML handling).
  */
 
+#include <mutex>
 #include <string>
 #include <vector>
 #include <set>
@@ -66,6 +67,7 @@ public:
                     ASSET_COUNT};
 
 private:
+    mutable std::mutex m_file_system_lock;
 
     /** The names of the various subdirectories of the asset types. */
     std::vector< std::string > m_subdir_name;