diff --git a/daggy/include/daggy/dagloggers/FileSystemLogger.hpp b/daggy/include/daggy/dagloggers/FileSystemLogger.hpp
index 75d9d23..a166d7e 100644
--- a/daggy/include/daggy/dagloggers/FileSystemLogger.hpp
+++ b/daggy/include/daggy/dagloggers/FileSystemLogger.hpp
@@ -47,9 +47,13 @@ namespace daggy {
 
     private:
         fs::path root_;
+        std::atomic<DAGRunID> nextRunID_;
         std::mutex lock_;
 
-        const fs::path getCurrentPath() const;
-        const fs::path getRunsRoot() const;
+        std::unordered_map<fs::path, std::mutex> runLocks;
+
+        inline const fs::path getCurrentPath() const;
+        inline const fs::path getRunsRoot() const;
+        inline const fs::path getRunRoot(DAGRunID runID) const;
     };
 }
diff --git a/daggy/src/dagloggers/FileSystemLogger.cpp b/daggy/src/dagloggers/FileSystemLogger.cpp
index 390f615..d37315d 100644
--- a/daggy/src/dagloggers/FileSystemLogger.cpp
+++ b/daggy/src/dagloggers/FileSystemLogger.cpp
@@ -3,20 +3,39 @@
 namespace fs = std::filesystem;
 
 namespace daggy {
-    const fs::path FileSystemLogger::getCurrentPath() const { return root_ / "current"; }
-    const fs::path FileSystemLogger::getRunsRoot() const { return root_ / "runs"; }
+    inline const fs::path FileSystemLogger::getCurrentPath() const { return root_ / "current"; }
+    inline const fs::path FileSystemLogger::getRunsRoot() const { return root_ / "runs"; }
+    inline const fs::path getRunRoot(DAGRunID runID) const { return getRunsRoot() / std::to_string(runID); }
 
     FileSystemLogger(fs::path root)
     : root_(root)
+    , nextRunID_(0)
     {
-        std::vector<fs::paths> reqPaths{ root_, getCurrentPath(), getRunsRoot()};
-        for (const path : reqPaths) {
+        const std::vector<fs::paths> reqPaths{ root_, getCurrentPath(), getRunsRoot()};
+        for (const auto & path : reqPaths) {
             if (! fs::exists(path)) { fs::create_directory(path); }
         }
+
+        // Get the next run ID
+        size_t runID = 0;
+        for (auto & dir : fs::std::filesystem::directory_iterator(getRunsRoot())) {
+            try {
+                runID = std::stoull(dir.stem());
+                if (runID > nextRunID_) nextRunID_ = runID + 1;
+            } catch {}
+        }
     }
 
     // Execution
-    DAGRunID FileSystemLogger::startDAGRun(std::string name, const std::vector<Task> & tasks){ }
+    DAGRunID FileSystemLogger::startDAGRun(std::string name, const std::vector<Task> & tasks){
+        DAGRunID runID = nextRunID_++;
+
+        // TODO make this threadsafe
+        fs::path runDir = getRunRoot(runID);
+        std::lock_guard<std::mutex> guard(runLocks[runDir]);
+
+        // Init the directory
+    }
     void FileSystemLogger::updateDAGRunState(DAGRunID dagRunId, RunState state){ }
     void FileSystemLogger::logTaskAttempt(DAGRunID, size_t taskID, const AttemptRecord & attempt){ }
     void FileSystemLogger::markTaskComplete(DAGRunID dagRun, size_t taskID){ }