diff --git a/arduino-core/src/processing/app/debug/Compiler.java b/arduino-core/src/processing/app/debug/Compiler.java
index a3a42487fe8..ccbc329b500 100644
--- a/arduino-core/src/processing/app/debug/Compiler.java
+++ b/arduino-core/src/processing/app/debug/Compiler.java
@@ -395,6 +395,7 @@ public boolean compile(boolean _verbose, boolean _save) throws RunnerException,
     progressListener.progress(20);
     List<File> includeFolders = new ArrayList<File>();
     includeFolders.add(prefs.getFile("build.core.path"));
+    includeFolders.add(sketch.getFolder());
     if (prefs.getFile("build.variant.path") != null)
       includeFolders.add(prefs.getFile("build.variant.path"));
     for (UserLibrary lib : importedLibraries) {