diff --git a/CHANGELOG.md b/CHANGELOG.md
index 866e8dd62..254e55d43 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@
 * Support label references to user defined listings environment
 * Add option to disable automatic compilation in power save mode
 * Convert automatic compilation settings to a combobox
+* Add experimental support for the addtoluatexpath package
 * Add checkboxes to graphic insertion wizard for relative width or height
 
 ### Fixed
diff --git a/src/nl/hannahsten/texifyidea/index/file/LatexIndexableSetContributor.kt b/src/nl/hannahsten/texifyidea/index/file/LatexIndexableSetContributor.kt
index 70aef3cd7..56be336e5 100644
--- a/src/nl/hannahsten/texifyidea/index/file/LatexIndexableSetContributor.kt
+++ b/src/nl/hannahsten/texifyidea/index/file/LatexIndexableSetContributor.kt
@@ -14,6 +14,7 @@ import nl.hannahsten.texifyidea.index.LatexIncludesIndex
 import nl.hannahsten.texifyidea.settings.TexifySettings
 import nl.hannahsten.texifyidea.settings.sdk.LatexSdkUtil
 import nl.hannahsten.texifyidea.util.Log
+import nl.hannahsten.texifyidea.util.files.addToLuatexPathSearchDirectories
 import nl.hannahsten.texifyidea.util.getTexinputsPaths
 import nl.hannahsten.texifyidea.util.isTestProject
 import nl.hannahsten.texifyidea.util.magic.CommandMagic
@@ -76,8 +77,8 @@ class LatexIndexableSetContributor : IndexableSetContributor() {
 
         // Using the index while building it may be problematic, cache the result and hope it doesn't create too much trouble
         if (Cache.externalDirectFileInclusions == null && !DumbService.isDumb(project)) {
-            runInBackground(project, "Searching for external bib files...") {
-                // For now, just do this for bibliography and direct input commands, as there this is most common
+            runInBackground(project, "Searching for inclusions by absolute path...") {
+                // Bibliography and direct input commands
                 val commandNames = CommandMagic.includeOnlyExtensions.entries.filter { it.value.contains("bib") || it.value.contains("tex") }.map { it.key }.toSet()
                 val externalFiles = runReadAction {
                     LatexIncludesIndex.Util.getCommandsByNames(commandNames, project, GlobalSearchScope.projectScope(project))
@@ -93,6 +94,12 @@ class LatexIndexableSetContributor : IndexableSetContributor() {
                         }
                         runReadAction { file?.parent }
                     }
+                    .toMutableList()
+
+                // addtoluatexpath package
+                val luatexPathDirectories = addToLuatexPathSearchDirectories(project)
+                externalFiles.addAll(luatexPathDirectories)
+
                 Cache.externalDirectFileInclusions = externalFiles.toSet()
             }
         }
diff --git a/src/nl/hannahsten/texifyidea/lang/LatexPackage.kt b/src/nl/hannahsten/texifyidea/lang/LatexPackage.kt
index bc42d7481..9bd6f315c 100644
--- a/src/nl/hannahsten/texifyidea/lang/LatexPackage.kt
+++ b/src/nl/hannahsten/texifyidea/lang/LatexPackage.kt
@@ -27,6 +27,7 @@ open class LatexPackage @JvmOverloads constructor(
         // Predefined packages.
         val DEFAULT = LatexPackage("")
 
+        val ADDTOLUATEXPATH = LatexPackage("addtoluatexpath")
         val ALGORITHM2E = LatexPackage("algorithm2e")
         val ALGORITHMICX = LatexPackage("algorithmicx")
         val ALGPSEUDOCODE = LatexPackage("algpseudocode")
diff --git a/src/nl/hannahsten/texifyidea/lang/commands/LatexGenericRegularCommand.kt b/src/nl/hannahsten/texifyidea/lang/commands/LatexGenericRegularCommand.kt
index ae9658d81..559a0d3f1 100644
--- a/src/nl/hannahsten/texifyidea/lang/commands/LatexGenericRegularCommand.kt
+++ b/src/nl/hannahsten/texifyidea/lang/commands/LatexGenericRegularCommand.kt
@@ -32,6 +32,7 @@ enum class LatexGenericRegularCommand(
 ) : LatexCommand {
 
     ADDTOCOUNTER("addtocounter", "countername".asRequired(), "value".asRequired()),
+    ADDTOLUATEXPATH("addtoluatexpath", RequiredFolderArgument("paths")),
     A_RING("aa", display = "å"),
     CAPITAL_A_RING("AA", display = "Å"),
     ADDBIBRESOURCE("addbibresource", RequiredFileArgument("bibliographyfile", true, false, "bib"), dependency = BIBLATEX),
diff --git a/src/nl/hannahsten/texifyidea/reference/InputFileReference.kt b/src/nl/hannahsten/texifyidea/reference/InputFileReference.kt
index 55d1b802d..529f0a471 100644
--- a/src/nl/hannahsten/texifyidea/reference/InputFileReference.kt
+++ b/src/nl/hannahsten/texifyidea/reference/InputFileReference.kt
@@ -202,6 +202,14 @@ class InputFileReference(
             targetFile = findAnywhereInProject(processedKey)
         }
 
+        // addtoluatexpath package
+        if (targetFile == null) {
+            for (path in addToLuatexPathSearchDirectories(element.project)) {
+                targetFile = path.findFile(processedKey, extensions, supportsAnyExtension)
+                if (targetFile != null) break
+            }
+        }
+
         if (targetFile == null) return null
 
         // Return a reference to the target file.
diff --git a/src/nl/hannahsten/texifyidea/util/files/FileSet.kt b/src/nl/hannahsten/texifyidea/util/files/FileSet.kt
index 23a97dc98..0260bfd02 100644
--- a/src/nl/hannahsten/texifyidea/util/files/FileSet.kt
+++ b/src/nl/hannahsten/texifyidea/util/files/FileSet.kt
@@ -1,13 +1,22 @@
 package nl.hannahsten.texifyidea.util.files
 
 import com.intellij.openapi.application.runReadAction
+import com.intellij.openapi.project.Project
+import com.intellij.openapi.vfs.LocalFileSystem
+import com.intellij.openapi.vfs.VirtualFile
 import com.intellij.psi.PsiFile
+import com.intellij.psi.search.GlobalSearchScope
 import nl.hannahsten.texifyidea.index.BibtexEntryIndex
 import nl.hannahsten.texifyidea.index.LatexCommandsIndex
 import nl.hannahsten.texifyidea.index.LatexDefinitionIndex
 import nl.hannahsten.texifyidea.index.LatexIncludesIndex
+import nl.hannahsten.texifyidea.lang.LatexPackage
+import nl.hannahsten.texifyidea.lang.commands.LatexGenericRegularCommand
 import nl.hannahsten.texifyidea.psi.LatexCommands
+import nl.hannahsten.texifyidea.util.magic.CommandMagic
+import nl.hannahsten.texifyidea.util.magic.cmd
 import nl.hannahsten.texifyidea.util.parser.isDefinition
+import nl.hannahsten.texifyidea.util.parser.requiredParameter
 
 /**
  * Finds all the files in the project that are somehow related using includes.
@@ -95,3 +104,30 @@ fun PsiFile.definitionsInFileSet(): Collection<LatexCommands> {
 fun PsiFile.definitionsAndRedefinitionsInFileSet(): Collection<LatexCommands> {
     return LatexDefinitionIndex.Util.getItemsInFileSet(this)
 }
+
+/**
+ * The addtoluatexpath package supports adding to \input@path in different ways
+ */
+fun addToLuatexPathSearchDirectories(project: Project): List<VirtualFile> {
+    val direct = runReadAction { LatexCommandsIndex.Util.getCommandsByNames(setOf(LatexGenericRegularCommand.ADDTOLUATEXPATH.cmd), project, GlobalSearchScope.projectScope(project)) }
+        .mapNotNull { command -> runReadAction { command.requiredParameter(0) } }
+        .flatMap { it.split(",") }
+    val viaUsepackage = runReadAction { LatexIncludesIndex.Util.getCommandsByNames(CommandMagic.packageInclusionCommands, project, GlobalSearchScope.projectScope(project)) }
+        .filter { runReadAction { it.requiredParameter(0) } == LatexPackage.ADDTOLUATEXPATH.name }
+        .flatMap { runReadAction { it.getOptionalParameterMap().keys } }
+        .flatMap { it.text.split(",") }
+
+    val luatexPathDirectories = (direct + viaUsepackage).flatMap {
+        val basePath = LocalFileSystem.getInstance().findFileByPath(it.trimEnd('/', '*')) ?: return@flatMap emptyList()
+        if (it.endsWith("/**")) {
+            basePath.allChildDirectories()
+        }
+        else if (it.endsWith("/*")) {
+            basePath.children.filter { it.isDirectory }
+        }
+        else {
+            listOf(basePath)
+        }
+    }
+    return luatexPathDirectories
+}