diff --git a/org.eclipse.lsp4xml/src/main/java/org/eclipse/lsp4xml/extensions/xsi/XSICompletionParticipant.java b/org.eclipse.lsp4xml/src/main/java/org/eclipse/lsp4xml/extensions/xsi/XSICompletionParticipant.java
index f9e345fb34..5dfef69845 100644
--- a/org.eclipse.lsp4xml/src/main/java/org/eclipse/lsp4xml/extensions/xsi/XSICompletionParticipant.java
+++ b/org.eclipse.lsp4xml/src/main/java/org/eclipse/lsp4xml/extensions/xsi/XSICompletionParticipant.java
@@ -26,10 +26,10 @@ public class XSICompletionParticipant extends CompletionParticipantAdapter {
 	@Override
 	public void onAttributeName(boolean generateValue, Range fullRange, ICompletionRequest request,
 			ICompletionResponse response) throws Exception {
-		if (request.getXMLDocument().hasSchemaInstancePrefix()) {
+		//if (request.getXMLDocument().hasSchemaInstancePrefix()) {
 			XSISchemaModel.computeCompletionResponses(request, response, fullRange, request.getXMLDocument(),
 					generateValue);
-		}
+		
 	}
 
 	@Override
diff --git a/org.eclipse.lsp4xml/src/main/java/org/eclipse/lsp4xml/services/XSISchemaModel.java b/org.eclipse.lsp4xml/src/main/java/org/eclipse/lsp4xml/services/XSISchemaModel.java
index 9ee7fc7844..065fe1307f 100644
--- a/org.eclipse.lsp4xml/src/main/java/org/eclipse/lsp4xml/services/XSISchemaModel.java
+++ b/org.eclipse.lsp4xml/src/main/java/org/eclipse/lsp4xml/services/XSISchemaModel.java
@@ -16,18 +16,14 @@
 import org.eclipse.lsp4j.CompletionItem;
 import org.eclipse.lsp4j.CompletionItemKind;
 import org.eclipse.lsp4j.Hover;
-import org.eclipse.lsp4j.InsertTextFormat;
 import org.eclipse.lsp4j.MarkupContent;
 import org.eclipse.lsp4j.MarkupKind;
-import org.eclipse.lsp4j.Position;
 import org.eclipse.lsp4j.Range;
 import org.eclipse.lsp4j.TextEdit;
 import org.eclipse.lsp4xml.commons.BadLocationException;
 import org.eclipse.lsp4xml.dom.DOMAttr;
 import org.eclipse.lsp4xml.dom.DOMDocument;
 import org.eclipse.lsp4xml.dom.DOMElement;
-import org.eclipse.lsp4xml.dom.DOMNode;
-import org.eclipse.lsp4xml.extensions.contentmodel.utils.XMLGenerator;
 import org.eclipse.lsp4xml.services.extensions.ICompletionRequest;
 import org.eclipse.lsp4xml.services.extensions.ICompletionResponse;
 import org.eclipse.lsp4xml.services.extensions.IHoverRequest;
@@ -64,6 +60,8 @@ public class XSISchemaModel {
 				"  <!-- ... -->  " + lineSeparator +
 				"</root>  " + lineSeparator +
 				"```" ;
+	public static final String XSI_WEBSITE = "http://www.w3.org/2001/XMLSchema-instance";
+	public static final String XSI_DOC = "The namespace that defines important attributes such as `noNamespaceSchemaLocation` and `schemaLocation`.";
 	public static void computeCompletionResponses(ICompletionRequest request, 
 			ICompletionResponse response, Range editRange, DOMDocument document, boolean generateValue) throws BadLocationException {
 		
@@ -74,8 +72,13 @@ public static void computeCompletionResponses(ICompletionRequest request,
 		if(rootElement.equals(nodeAtOffset)) {
 			inRootElement = true;
 		}
-		
+
 		boolean isSnippetsSupported = request.getCompletionSettings().isCompletionSnippetsSupported();
+		if(inRootElement && document.hasSchemaInstancePrefix() == false) {
+			createCompletionItem("xmlns:xsi", isSnippetsSupported, generateValue, editRange, XSI_WEBSITE, null, XSI_DOC, response);	
+			return;
+		}
+		
 		String actualPrefix = document.getSchemaInstancePrefix();
 		String name;
 		String documentation;
@@ -100,14 +103,16 @@ public static void computeCompletionResponses(ICompletionRequest request,
 		}
 		//The xsi:schemaLocation and xsi:noNamespaceSchemaLocation attributes can be used in a document 
 		//to provide hints as to the physical location of schema documents which may be used for ·assessment·.
-		if(inRootElement && !schemaLocationExists && !noNamespaceSchemaLocationExists) {
-			documentation = SCHEMA_LOCATION_DOC;
-			name = actualPrefix + ":schemaLocation";
-			createCompletionItem(name, isSnippetsSupported, generateValue, editRange, null, null, documentation, response);	
-			
-			documentation = NO_NAMESPACE_SCHEMA_LOCATION_DOC;
-			name = actualPrefix + ":noNamespaceSchemaLocation";
-			createCompletionItem(name, isSnippetsSupported, generateValue, editRange, null, null, documentation, response);		
+		if(inRootElement) {
+			if(!schemaLocationExists && !noNamespaceSchemaLocationExists) {
+				documentation = SCHEMA_LOCATION_DOC;
+				name = actualPrefix + ":schemaLocation";
+				createCompletionItem(name, isSnippetsSupported, generateValue, editRange, null, null, documentation, response);	
+				
+				documentation = NO_NAMESPACE_SCHEMA_LOCATION_DOC;
+				name = actualPrefix + ":noNamespaceSchemaLocation";
+				createCompletionItem(name, isSnippetsSupported, generateValue, editRange, null, null, documentation, response);	
+			}	
 		}
 	}
 
@@ -129,12 +134,21 @@ public static void computeValueCompletionResponses(ICompletionRequest request,
 		int offset = document.offsetAt(editRange.getStart());
 		DOMElement nodeAtOffset = (DOMElement) document.findNodeAt(offset);
 		
+		
 		String actualPrefix = document.getSchemaInstancePrefix();
+		DOMAttr attrAtOffset = nodeAtOffset.findAttrAt(offset);
+		String attrName = attrAtOffset.getName();
 		
-		// Value completion for 'nil' attribute
-		DOMAttr nilAttr = nodeAtOffset.getAttributeNode(actualPrefix, "nil");
-		if(nilAttr != null) {
-			createCompletionItemsForValues(StringUtils.TRUE_FALSE_ARRAY, editRange, document, response, settings);
+		if(attrName != null) {
+			if(attrName.equals(actualPrefix + ":nil")) { // Value completion for 'nil' attribute
+				createCompletionItemsForValues(StringUtils.TRUE_FALSE_ARRAY, editRange, document, response, settings);
+			}
+			else if(document.getDocumentElement().equals(nodeAtOffset)) { // if in the root element
+				if(attrName.equals("xmlns:xsi")) {
+					createSingleCompletionItemForValue(XSI_WEBSITE, editRange, document, response, settings);
+				}
+			}
+			
 		}
 	}
 
diff --git a/org.eclipse.lsp4xml/src/test/java/org/eclipse/lsp4xml/extensions/contentmodel/XMLSchemaCompletionExtensionsTest.java b/org.eclipse.lsp4xml/src/test/java/org/eclipse/lsp4xml/extensions/contentmodel/XMLSchemaCompletionExtensionsTest.java
index 1e8bfc829f..97795b2e97 100644
--- a/org.eclipse.lsp4xml/src/test/java/org/eclipse/lsp4xml/extensions/contentmodel/XMLSchemaCompletionExtensionsTest.java
+++ b/org.eclipse.lsp4xml/src/test/java/org/eclipse/lsp4xml/extensions/contentmodel/XMLSchemaCompletionExtensionsTest.java
@@ -452,7 +452,7 @@ public void xsiCompletionNotUsingXSIName() throws BadLocationException {
 	}
 
 	@Test
-	public void xsiCompletionDoesntAppearSinceDoesntExist() throws BadLocationException {
+	public void xmlnsXSICompletion() throws BadLocationException {
 		String xml = 
 		"<project\r\n" +
 		"    xmlns=\"http://maven.apache.org/POM/4.0.0\"\r\n" +
@@ -460,7 +460,19 @@ public void xsiCompletionDoesntAppearSinceDoesntExist() throws BadLocationExcept
 		"  <modelVersion></modelVersion>\r\n" +
 		"</project>";
 
-		XMLAssert.testCompletionFor(xml, 0);
+		XMLAssert.testCompletionFor(xml, 1, c("xmlns:xsi", "xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\""));
+	}
+
+	@Test
+	public void xmlnsXSIValueCompletion() throws BadLocationException {
+		String xml = 
+		"<project\r\n" +
+		"    xmlns=\"http://maven.apache.org/POM/4.0.0\"\r\n" +
+		"    xmlns:xsi=|>\r\n" +
+		"  <modelVersion></modelVersion>\r\n" +
+		"</project>";
+
+		XMLAssert.testCompletionFor(xml, 1, c("http://www.w3.org/2001/XMLSchema-instance", "\"http://www.w3.org/2001/XMLSchema-instance\""));
 	}
 
 	@Test