diff --git a/README.md b/README.md
index ee524bc..14d4e1b 100644
--- a/README.md
+++ b/README.md
@@ -90,6 +90,10 @@ weak warnings as missing macro evaluation will not resolve symbols defined via `
 
 Provides the assigned value of a `=`, `set` or `equ` symbol definition when hovering over a symbol.
 
+#### M68kMacroDefinition
+
+When used over a macro invocation, shows the expanded macro contents.
+
 #### M68kLabel
 
 Shows the comments above the label (local or global) and an end-of-line comment, if available. If the first statement after the label is a directive
@@ -160,6 +164,7 @@ are appreciated. It really is keeping me motivated to continue development.
 
 - Enhancement: Label documentation now also works for local labels and includes end-of-line comment for label, too.
 - Enhancement: Symbol definition documentation now also includes comments in the same way as the label documentation does.
+- New: Macro definition / invocation documentation provider that even tries to expand macros.
 
 ### V0.7 (26-Sep-21)
 
diff --git a/build.gradle b/build.gradle
index 41a97ac..2f8f26b 100644
--- a/build.gradle
+++ b/build.gradle
@@ -62,6 +62,7 @@ patchPluginXml {
     <ul>
       <li>Enhancement: Label documentation now also works for local labels and includes end-of-line comment for label, too.
       <li>Enhancement: Symbol definition documentation now also includes comments in the same way as the label documentation does.
+      <li>New: Macro definition / invocation documentation provider that even tries to expand macros.
     </ul>
   <p>Full changelog available at <a href="https://github.com/chrisly42/mc68000-asm-plugin#changelog">Github project site</a>.</p>
 """)
diff --git a/src/main/java/de/platon42/intellij/plugins/m68k/documentation/AbstractM68kDocumentationProvider.kt b/src/main/java/de/platon42/intellij/plugins/m68k/documentation/AbstractM68kDocumentationProvider.kt
index 032cf3f..da64798 100644
--- a/src/main/java/de/platon42/intellij/plugins/m68k/documentation/AbstractM68kDocumentationProvider.kt
+++ b/src/main/java/de/platon42/intellij/plugins/m68k/documentation/AbstractM68kDocumentationProvider.kt
@@ -6,7 +6,7 @@ import com.intellij.openapi.util.text.HtmlBuilder
 import com.intellij.openapi.util.text.HtmlChunk
 import com.intellij.psi.PsiElement
 import de.platon42.intellij.plugins.m68k.psi.M68kNamedElement
-import de.platon42.intellij.plugins.m68k.psi.M68kPsiWalkUtil
+import de.platon42.intellij.plugins.m68k.psi.utils.M68kPsiWalkUtil
 
 abstract class AbstractM68kDocumentationProvider : AbstractDocumentationProvider() {
 
@@ -27,6 +27,9 @@ abstract class AbstractM68kDocumentationProvider : AbstractDocumentationProvider
     fun getContent(element: PsiElement) =
         HtmlBuilder().append(HtmlChunk.text(element.text).code()).wrapWith(DocumentationMarkup.CONTENT_ELEMENT)
 
+    fun getContent(chunk: HtmlChunk) =
+        HtmlBuilder().append(chunk).wrapWith(DocumentationMarkup.CONTENT_ELEMENT)
+
     fun getContent(value: String) =
         HtmlBuilder().append(value).wrapWith(DocumentationMarkup.CONTENT_ELEMENT)
 }
\ No newline at end of file
diff --git a/src/main/java/de/platon42/intellij/plugins/m68k/documentation/M68kMacroDefinitionDocumentationProvider.kt b/src/main/java/de/platon42/intellij/plugins/m68k/documentation/M68kMacroDefinitionDocumentationProvider.kt
new file mode 100644
index 0000000..7fe0a93
--- /dev/null
+++ b/src/main/java/de/platon42/intellij/plugins/m68k/documentation/M68kMacroDefinitionDocumentationProvider.kt
@@ -0,0 +1,42 @@
+package de.platon42.intellij.plugins.m68k.documentation
+
+import com.intellij.openapi.util.text.HtmlBuilder
+import com.intellij.openapi.util.text.HtmlChunk
+import com.intellij.psi.PsiElement
+import com.intellij.psi.util.PsiTreeUtil
+import de.platon42.intellij.plugins.m68k.psi.M68kMacroCall
+import de.platon42.intellij.plugins.m68k.psi.M68kMacroDefinition
+import de.platon42.intellij.plugins.m68k.psi.utils.M68kMacroExpansionUtil
+
+class M68kMacroDefinitionDocumentationProvider : AbstractM68kDocumentationProvider() {
+
+    override fun getQuickNavigateInfo(element: PsiElement, originalElement: PsiElement?): String? {
+        return generateDoc(element, originalElement)
+    }
+
+    override fun generateDoc(element: PsiElement, originalElement: PsiElement?): String? {
+        return if (element is M68kMacroDefinition) createDoc(element, originalElement, 100) else null // TODO make this configurable
+    }
+
+    override fun generateHoverDoc(element: PsiElement, originalElement: PsiElement?): String? {
+        return if (element is M68kMacroDefinition) createDoc(element, originalElement, 4) else null // TODO make this configurable
+    }
+
+    private fun createDoc(macrodef: M68kMacroDefinition, originalElement: PsiElement?, linesLimit: Int): String {
+        val macroCall = PsiTreeUtil.getParentOfType(originalElement, M68kMacroCall::class.java)
+        val expandedMacro = M68kMacroExpansionUtil.expandMacro(macrodef, macroCall)
+        val builder = HtmlBuilder()
+        return builder
+            .append(getComments(macrodef))
+            .append(getDefinition(HtmlChunk.text(macrodef.name!!).code()))
+            .append(
+                getContent(
+                    HtmlBuilder().appendWithSeparators(
+                        HtmlChunk.br(),
+                        expandedMacro.take(linesLimit).map { HtmlChunk.text(it).code() }.toList()
+                    ).toFragment()
+                )
+            )
+            .toString()
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/de/platon42/intellij/plugins/m68k/psi/M68kLookupUtil.kt b/src/main/java/de/platon42/intellij/plugins/m68k/psi/utils/M68kLookupUtil.kt
similarity index 98%
rename from src/main/java/de/platon42/intellij/plugins/m68k/psi/M68kLookupUtil.kt
rename to src/main/java/de/platon42/intellij/plugins/m68k/psi/utils/M68kLookupUtil.kt
index 74c01f3..bee4b48 100644
--- a/src/main/java/de/platon42/intellij/plugins/m68k/psi/M68kLookupUtil.kt
+++ b/src/main/java/de/platon42/intellij/plugins/m68k/psi/utils/M68kLookupUtil.kt
@@ -1,9 +1,10 @@
-package de.platon42.intellij.plugins.m68k.psi
+package de.platon42.intellij.plugins.m68k.psi.utils
 
 import com.intellij.openapi.project.Project
 import com.intellij.psi.search.GlobalSearchScope
 import com.intellij.psi.stubs.StubIndex
 import com.intellij.psi.util.PsiTreeUtil
+import de.platon42.intellij.plugins.m68k.psi.*
 import de.platon42.intellij.plugins.m68k.stubs.M68kGlobalLabelStubIndex
 import de.platon42.intellij.plugins.m68k.stubs.M68kMacroDefinitionStubIndex
 import de.platon42.intellij.plugins.m68k.stubs.M68kSymbolDefinitionStubIndex
diff --git a/src/main/java/de/platon42/intellij/plugins/m68k/psi/utils/M68kMacroExpansionUtil.kt b/src/main/java/de/platon42/intellij/plugins/m68k/psi/utils/M68kMacroExpansionUtil.kt
new file mode 100644
index 0000000..165c907
--- /dev/null
+++ b/src/main/java/de/platon42/intellij/plugins/m68k/psi/utils/M68kMacroExpansionUtil.kt
@@ -0,0 +1,25 @@
+package de.platon42.intellij.plugins.m68k.psi.utils
+
+import de.platon42.intellij.plugins.m68k.psi.M68kMacroCall
+import de.platon42.intellij.plugins.m68k.psi.M68kMacroDefinition
+
+object M68kMacroExpansionUtil {
+
+    fun expandMacro(macroDefinition: M68kMacroDefinition, macroCall: M68kMacroCall?): List<String> {
+        val params = macroCall?.exprList?.map { it.text }?.toTypedArray() ?: emptyArray()
+
+        if (params.isEmpty()) return macroDefinition.macroPlainLineList.map { it.text }
+
+        val originalContent = macroDefinition.macroPlainLineList.joinToString("\n", transform = { it.text })
+        var modifiedContent = originalContent
+        for (param in params.withIndex()) {
+            val paramRef = when (param.index) {
+                in 0..8 -> "\\" + (param.index + 1)
+                in 9..34 -> "\\" + ('a' + (param.index - 9))
+                else -> "seriously?"
+            }
+            modifiedContent = modifiedContent.replace(paramRef, param.value)
+        }
+        return modifiedContent.split("\n")
+    }
+}
\ No newline at end of file
diff --git a/src/main/java/de/platon42/intellij/plugins/m68k/psi/M68kPsiWalkUtil.kt b/src/main/java/de/platon42/intellij/plugins/m68k/psi/utils/M68kPsiWalkUtil.kt
similarity index 60%
rename from src/main/java/de/platon42/intellij/plugins/m68k/psi/M68kPsiWalkUtil.kt
rename to src/main/java/de/platon42/intellij/plugins/m68k/psi/utils/M68kPsiWalkUtil.kt
index 093a12b..a2c53aa 100644
--- a/src/main/java/de/platon42/intellij/plugins/m68k/psi/M68kPsiWalkUtil.kt
+++ b/src/main/java/de/platon42/intellij/plugins/m68k/psi/utils/M68kPsiWalkUtil.kt
@@ -1,16 +1,23 @@
-package de.platon42.intellij.plugins.m68k.psi
+package de.platon42.intellij.plugins.m68k.psi.utils
 
 import com.intellij.psi.PsiComment
 import com.intellij.psi.PsiElement
 import com.intellij.psi.util.PsiTreeUtil
 import com.intellij.util.SmartList
 import com.intellij.util.containers.addIfNotNull
+import de.platon42.intellij.plugins.m68k.psi.M68kMacroDefinition
 
 object M68kPsiWalkUtil {
 
     fun collectRelatedComments(element: PsiElement): List<PsiComment> {
         val comments = SmartList<PsiComment>()
-        val eolComment = PsiTreeUtil.skipWhitespacesForward(element) as? PsiComment
+        val eolComment = if (element is M68kMacroDefinition) {
+            // macro definition needs special handling of EOL comments
+            PsiTreeUtil.findChildOfType(element, PsiComment::class.java)
+        } else {
+            PsiTreeUtil.skipWhitespacesForward(element) as? PsiComment
+        }
+
         comments.addIfNotNull(eolComment)
         var prevToken: PsiElement? = element
         do {
diff --git a/src/main/java/de/platon42/intellij/plugins/m68k/refs/M68kGlobalLabelSymbolCompletionContributor.kt b/src/main/java/de/platon42/intellij/plugins/m68k/refs/M68kGlobalLabelSymbolCompletionContributor.kt
index 174aec5..9254e49 100644
--- a/src/main/java/de/platon42/intellij/plugins/m68k/refs/M68kGlobalLabelSymbolCompletionContributor.kt
+++ b/src/main/java/de/platon42/intellij/plugins/m68k/refs/M68kGlobalLabelSymbolCompletionContributor.kt
@@ -6,8 +6,8 @@ import com.intellij.codeInsight.lookup.LookupElementBuilder
 import com.intellij.patterns.PlatformPatterns
 import com.intellij.util.ProcessingContext
 import de.platon42.intellij.plugins.m68k.M68kIcons
-import de.platon42.intellij.plugins.m68k.psi.M68kLookupUtil
 import de.platon42.intellij.plugins.m68k.psi.M68kTypes
+import de.platon42.intellij.plugins.m68k.psi.utils.M68kLookupUtil
 
 class M68kGlobalLabelSymbolCompletionContributor : CompletionContributor() {
 
diff --git a/src/main/java/de/platon42/intellij/plugins/m68k/refs/M68kMacroCallCompletionContributor.kt b/src/main/java/de/platon42/intellij/plugins/m68k/refs/M68kMacroCallCompletionContributor.kt
index c87369f..9df0456 100644
--- a/src/main/java/de/platon42/intellij/plugins/m68k/refs/M68kMacroCallCompletionContributor.kt
+++ b/src/main/java/de/platon42/intellij/plugins/m68k/refs/M68kMacroCallCompletionContributor.kt
@@ -4,8 +4,8 @@ import com.intellij.codeInsight.completion.*
 import com.intellij.codeInsight.lookup.LookupElementBuilder
 import com.intellij.patterns.PlatformPatterns
 import com.intellij.util.ProcessingContext
-import de.platon42.intellij.plugins.m68k.psi.M68kLookupUtil
 import de.platon42.intellij.plugins.m68k.psi.M68kTypes
+import de.platon42.intellij.plugins.m68k.psi.utils.M68kLookupUtil
 
 class M68kMacroCallCompletionContributor : CompletionContributor() {
 
diff --git a/src/main/java/de/platon42/intellij/plugins/m68k/structureview/M68kStructureViewElement.kt b/src/main/java/de/platon42/intellij/plugins/m68k/structureview/M68kStructureViewElement.kt
index 461f911..7371209 100644
--- a/src/main/java/de/platon42/intellij/plugins/m68k/structureview/M68kStructureViewElement.kt
+++ b/src/main/java/de/platon42/intellij/plugins/m68k/structureview/M68kStructureViewElement.kt
@@ -6,8 +6,8 @@ import com.intellij.navigation.ItemPresentation
 import com.intellij.psi.NavigatablePsiElement
 import de.platon42.intellij.plugins.m68k.psi.M68kFile
 import de.platon42.intellij.plugins.m68k.psi.M68kGlobalLabel
-import de.platon42.intellij.plugins.m68k.psi.M68kLookupUtil
-import de.platon42.intellij.plugins.m68k.psi.M68kLookupUtil.findAllLocalLabels
+import de.platon42.intellij.plugins.m68k.psi.utils.M68kLookupUtil
+import de.platon42.intellij.plugins.m68k.psi.utils.M68kLookupUtil.findAllLocalLabels
 
 class M68kStructureViewElement(private val myElement: NavigatablePsiElement) : StructureViewTreeElement {
     override fun getValue(): Any = myElement
diff --git a/src/main/resources/META-INF/plugin.xml b/src/main/resources/META-INF/plugin.xml
index 4512213..0255fbe 100644
--- a/src/main/resources/META-INF/plugin.xml
+++ b/src/main/resources/META-INF/plugin.xml
@@ -41,6 +41,8 @@
                                     implementationClass="de.platon42.intellij.plugins.m68k.documentation.M68kSymbolDefinitionDocumentationProvider"/>
         <lang.documentationProvider language="MC68000"
                                     implementationClass="de.platon42.intellij.plugins.m68k.documentation.M68kLabelDocumentationProvider"/>
+        <lang.documentationProvider language="MC68000"
+                                    implementationClass="de.platon42.intellij.plugins.m68k.documentation.M68kMacroDefinitionDocumentationProvider"/>
         <lang.documentationProvider language="MC68000"
                                     implementationClass="de.platon42.intellij.plugins.m68k.documentation.M68kRegisterFlowDocumentationProvider"/>
         <lang.documentationProvider language="MC68000"
diff --git a/src/test/java/de/platon42/intellij/plugins/m68k/documentation/M68kMacroDefinitionDocumentationProviderTest.kt b/src/test/java/de/platon42/intellij/plugins/m68k/documentation/M68kMacroDefinitionDocumentationProviderTest.kt
new file mode 100644
index 0000000..baf2e9c
--- /dev/null
+++ b/src/test/java/de/platon42/intellij/plugins/m68k/documentation/M68kMacroDefinitionDocumentationProviderTest.kt
@@ -0,0 +1,58 @@
+package de.platon42.intellij.plugins.m68k.documentation
+
+import com.intellij.testFramework.fixtures.CodeInsightTestFixture
+import de.platon42.intellij.jupiter.LightCodeInsightExtension
+import de.platon42.intellij.jupiter.MyFixture
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.extension.ExtendWith
+
+@ExtendWith(LightCodeInsightExtension::class)
+internal class M68kMacroDefinitionDocumentationProviderTest : AbstractDocumentationProviderTest() {
+
+    @Test
+    internal fun check_expanded_documentation_for_a_macro_definition(@MyFixture myFixture: CodeInsightTestFixture) {
+        myFixture.configureByText(
+            "documentme.asm", """
+MOLV<caret>ANIA MACRO ; the bestest macro
+ move.l \1,d0
+ mulu   d0,d0
+ ENDM
+        """
+        )
+        assertThat(generateDocumentation(myFixture))
+            .isEqualTo("<span class=\"grayed\">; the bestest macro</span><div class=\"definition\"><code>MOLVANIA</code></div><div class=\"content\"><code> move.l \\1,d0</code><br/><code> mulu   d0,d0</code></div>")
+    }
+
+    @Test
+    internal fun check_expanded_documentation_for_a_macro_invocation(@MyFixture myFixture: CodeInsightTestFixture) {
+        myFixture.configureByText(
+            "documentme.asm", """
+MOLVANIA MACRO ; the bestest macro
+ move.l \1,d0
+ mulu   d0,d0
+ ENDM
+
+ MOLV<caret>ANIA d1
+        """
+        )
+        assertThat(generateDocumentation(myFixture))
+            .isEqualTo("<span class=\"grayed\">; the bestest macro</span><div class=\"definition\"><code>MOLVANIA</code></div><div class=\"content\"><code> move.l d1,d0</code><br/><code> mulu   d0,d0</code></div>")
+    }
+
+    @Test
+    internal fun check_expanded_documentation_for_a_macro_invocation_with_lots_of_params(@MyFixture myFixture: CodeInsightTestFixture) {
+        myFixture.configureByText(
+            "documentme.asm", """
+; compress nibbles
+DTW MACRO
+ dc.b ((\1)<<4)|(\2),((\3)<<4)|(\4),((\5)<<4)|(\6),((\7)<<4)|(\8),((\9)<<4)|(\a),((\b)<<4)|(\c),((\d)<<4)|(\e),((\f)<<4)|(\g)
+ ENDM
+
+ DTW<caret> 15,14,14,10,1,2,3,4,10,11,10,12,5,3,9,10
+        """
+        )
+        assertThat(generateDocumentation(myFixture))
+            .isEqualTo("<span class=\"grayed\">; compress nibbles</span><div class=\"definition\"><code>DTW</code></div><div class=\"content\"><code> dc.b ((15)&lt;&lt;4)|(14),((14)&lt;&lt;4)|(10),((1)&lt;&lt;4)|(2),((3)&lt;&lt;4)|(4),((10)&lt;&lt;4)|(11),((10)&lt;&lt;4)|(12),((5)&lt;&lt;4)|(3),((9)&lt;&lt;4)|(10)</code></div>")
+    }
+}
\ No newline at end of file