diff --git a/eclipse-language-servers/org.springframework.tooling.boot.ls/plugin.xml b/eclipse-language-servers/org.springframework.tooling.boot.ls/plugin.xml
index 6e01405b7..25b337b19 100644
--- a/eclipse-language-servers/org.springframework.tooling.boot.ls/plugin.xml
+++ b/eclipse-language-servers/org.springframework.tooling.boot.ls/plugin.xml
@@ -51,8 +51,8 @@
       </content-type>
       <file-association
             content-type="org.springframework.boot.ide.properties.application.yml"
-            file-names="application.yml,bootstrap.yml,application-dev.yml"
-            file-patterns="application-*.yml">
+            file-names="application.yml,bootstrap.yml,application-dev.yml,application.yaml,bootstrap.yaml,application-dev.yaml"
+            file-patterns="application-*.yml,application-*.yaml">
       </file-association>
    </extension>
 
diff --git a/headless-services/spring-boot-language-server/src/main/java/org/springframework/ide/vscode/boot/java/value/ValuePropertyReferencesProvider.java b/headless-services/spring-boot-language-server/src/main/java/org/springframework/ide/vscode/boot/java/value/ValuePropertyReferencesProvider.java
index 6011836aa..027740621 100644
--- a/headless-services/spring-boot-language-server/src/main/java/org/springframework/ide/vscode/boot/java/value/ValuePropertyReferencesProvider.java
+++ b/headless-services/spring-boot-language-server/src/main/java/org/springframework/ide/vscode/boot/java/value/ValuePropertyReferencesProvider.java
@@ -35,6 +35,7 @@ import org.eclipse.lsp4j.Position;
 import org.eclipse.lsp4j.Range;
 import org.eclipse.lsp4j.WorkspaceFolder;
 import org.springframework.ide.vscode.boot.java.handlers.ReferenceProvider;
+import org.springframework.ide.vscode.boot.properties.BootPropertiesLanguageServerComponents;
 import org.springframework.ide.vscode.commons.languageserver.util.SimpleLanguageServer;
 import org.springframework.ide.vscode.commons.util.BadLocationException;
 import org.springframework.ide.vscode.commons.util.text.TextDocument;
@@ -132,23 +133,30 @@ public class ValuePropertyReferencesProvider implements ReferenceProvider {
 	}
 
 	private boolean isPropertiesFile(Path path) {
-		Path fileName = path.getFileName();
+		String fileName = path.getFileName().toString();
 
-		if (fileName.toString().endsWith(".properties") || path.toString().endsWith(".yml")) {
-			return fileName.toString().contains("application");
-		}
-		else {
-			return false;
+		if (fileName.endsWith(BootPropertiesLanguageServerComponents.PROPERTIES)) {
+			return fileName.contains("application");
+		} else {
+			for (String yml : BootPropertiesLanguageServerComponents.YML) {
+				if (fileName.endsWith(yml)) {
+					return fileName.contains("application");
+				}
+			}
 		}
+		return false;
 	}
 
 	private List<Location> findReferences(Path path, String propertyKey) {
 		String filePath = path.toString();
-		if (filePath.endsWith(".properties")) {
+		if (filePath.endsWith(BootPropertiesLanguageServerComponents.PROPERTIES)) {
 			return findReferencesInPropertiesFile(filePath, propertyKey);
-		}
-		else if (filePath.endsWith(".yml")) {
-			return findReferencesInYMLFile(filePath, propertyKey);
+		} else {
+			for (String yml : BootPropertiesLanguageServerComponents.YML) {
+				if (filePath.endsWith(yml)) {
+					return findReferencesInYMLFile(filePath, propertyKey);
+				}
+			}
 		}
 		return new ArrayList<Location>();
 	}
diff --git a/headless-services/spring-boot-language-server/src/main/java/org/springframework/ide/vscode/boot/properties/BootPropertiesLanguageServerComponents.java b/headless-services/spring-boot-language-server/src/main/java/org/springframework/ide/vscode/boot/properties/BootPropertiesLanguageServerComponents.java
index 29b6428c4..32303e992 100644
--- a/headless-services/spring-boot-language-server/src/main/java/org/springframework/ide/vscode/boot/properties/BootPropertiesLanguageServerComponents.java
+++ b/headless-services/spring-boot-language-server/src/main/java/org/springframework/ide/vscode/boot/properties/BootPropertiesLanguageServerComponents.java
@@ -55,8 +55,8 @@ import com.google.common.collect.ImmutableSet;
  */
 public class BootPropertiesLanguageServerComponents implements LanguageServerComponents {
 
-	private static final String YML = ".yml";
-	private static final String PROPERTIES = ".properties";
+	public static final String[] YML = {".yml", ".yaml" } ;
+	public static final String PROPERTIES = ".properties";
 
 	private static final Set<LanguageId> LANGUAGES = ImmutableSet.of(
 			LanguageId.BOOT_PROPERTIES,
@@ -135,8 +135,12 @@ public class BootPropertiesLanguageServerComponents implements LanguageServerCom
 			if (uri!=null) {
 				if (uri.endsWith(PROPERTIES)) {
 					return propertiesCompletions.getCompletions(document, offset);
-				} else if (uri.endsWith(YML)) {
-					return yamlCompletions.getCompletions(document, offset);
+				} else {
+					for (String yml : YML) {
+						if (uri.endsWith(yml)) {
+							return yamlCompletions.getCompletions(document, offset);
+						}
+					}
 				}
 			}
 			return ImmutableList.of();
@@ -153,8 +157,12 @@ public class BootPropertiesLanguageServerComponents implements LanguageServerCom
 			if (uri!=null) {
 				if (uri.endsWith(PROPERTIES)) {
 					return propertiesHovers.getHoverInfo(document, offset);
-				} else if (uri.endsWith(YML)) {
-					return ymlHovers.getHoverInfo(document, offset);
+				} else {
+					for (String yml : YML) {
+						if (uri.endsWith(yml)) {
+							return ymlHovers.getHoverInfo(document, offset);
+						}
+					}
 				}
 			}
 			return null;
@@ -170,9 +178,13 @@ public class BootPropertiesLanguageServerComponents implements LanguageServerCom
 				if (uri.endsWith(PROPERTIES)) {
 					propertiesReconciler.reconcile(doc, problemCollector);
 					return;
-				} else if (uri.endsWith(YML)) {
-					ymlReconciler.reconcile(doc, problemCollector);
-					return;
+				} else {
+					for (String yml : YML) {
+						if (uri.endsWith(yml)) {
+							ymlReconciler.reconcile(doc, problemCollector);
+							return;
+						}
+					}
 				}
 			}
 			//No real reconciler is applicable. So tell the problemCollector there are no problems.