diff --git a/src/main/java/com/sshtools/tinytemplate/Templates.java b/src/main/java/com/sshtools/tinytemplate/Templates.java
index f8b3da9..d31eb12 100644
--- a/src/main/java/com/sshtools/tinytemplate/Templates.java
+++ b/src/main/java/com/sshtools/tinytemplate/Templates.java
@@ -642,6 +642,7 @@ public enum State {
 		public final static class Builder {
 			private boolean nullsAreEmpty = true;
 			private boolean missingThrowsException = true;
+			private boolean missingConditionIsFalse = true;
 			private Optional<Logger> logger = Optional.empty();
 			private Optional<VariableExpander> expander = Optional.empty();
 	
@@ -663,6 +664,11 @@ public Builder withMissingThrowsException(boolean missingThrowsException) {
 				return this;
 			}
 	
+			public Builder withMissingConditionIsFalse(boolean missingConditionIsFalse) {
+				this.missingConditionIsFalse = missingConditionIsFalse;
+				return this;
+			}
+	
 			public Builder withLogger(Logger logger) {
 				return withLogger(Optional.of(logger));
 			}
@@ -685,6 +691,7 @@ public TemplateProcessor build() {
 	
 		private final boolean nullsAreEmpty;
 		private final boolean missingThrowsException;
+		private final boolean missingConditionIsFalse;
 		private final Optional<Logger> logger;
 		private final Optional<VariableExpander> expander;
 		
@@ -736,6 +743,7 @@ private final static class Block {
 		private TemplateProcessor(Builder bldr) {
 			this.nullsAreEmpty = bldr.nullsAreEmpty;
 			this.missingThrowsException = bldr.missingThrowsException;
+			this.missingConditionIsFalse = bldr.missingConditionIsFalse;
 			this.logger = bldr.logger;
 			this.expander = bldr.expander;
 		}
@@ -960,7 +968,12 @@ private boolean processDirective(Block block, String directive) {
 				var match = false;
 				
 				if (conditionOr.isEmpty()) {
-					logger.ifPresent(l -> l.debug("Missing condition {0}, assuming {1}", condition.name, false));
+					if(!missingConditionIsFalse) {
+						if(missingThrowsException)
+							throw new IllegalStateException(MessageFormat.format("No condition in model named {0}.", condition.name));
+						else
+							logger.ifPresent(l -> l.warning("No condition in model named {0}, assuming {1}", condition.name, false));
+					}
 				} else {
 					match = conditionOr.get();
 				}
@@ -982,7 +995,10 @@ private boolean processDirective(Block block, String directive) {
 			else if(dir.equals("t:include")) {
 				var includeModel = block.model.includes.get(var);
 				if (includeModel == null) {
-					logger.ifPresent(l -> l.debug("No include in model named {0}", var));
+					if(missingThrowsException)
+						throw new IllegalStateException(MessageFormat.format("No include in model named {0}.", var));
+					else
+						logger.ifPresent(l -> l.warning("No include in model named {0}", var));
 					return false;
 				} else {
 					var include = includeModel.get();
@@ -1002,7 +1018,10 @@ else if(dir.equals("t:else")) {
 			else if(dir.equals("t:object")) {
 				var templateSupplier = block.model.templates.get(var);
 				if (templateSupplier == null) {
-					logger.ifPresent(l -> l.warning("Missing template {0} in message template", var));
+					if(missingThrowsException)
+						throw new IllegalStateException(MessageFormat.format("No object in model name {0}.", var));
+					else
+						logger.ifPresent(l -> l.warning("No object in model named {0}.", var));
 					return false;
 				}
 				else {
@@ -1030,7 +1049,10 @@ else if(dir.equals("t:object")) {
 			else if(dir.equals("t:list")) {
 				var listSupplier = block.model.lists.get(var);
 				if (listSupplier == null) {
-					logger.ifPresent(l -> l.warning("Missing list {0} in message template", var));
+					if(missingThrowsException)
+						throw new IllegalStateException(MessageFormat.format("No list in model named {0}.", var));
+					else
+						logger.ifPresent(l -> l.warning("No list in model named {0}", var));
 					return false;
 				}
 				else {
diff --git a/src/test/java/com/sshtools/tinytemplate/TemplatesTest.java b/src/test/java/com/sshtools/tinytemplate/TemplatesTest.java
index 88c62ac..a9cd630 100644
--- a/src/test/java/com/sshtools/tinytemplate/TemplatesTest.java
+++ b/src/test/java/com/sshtools/tinytemplate/TemplatesTest.java
@@ -304,7 +304,8 @@ public void testTemplateIf() {
 				</body>
 				</html>
 				 	 """).
-					condition("aCondition", true)));
+					condition("aCondition", true).
+					condition("bCondition", false)));
 	}
 	
 	@Test
@@ -383,7 +384,8 @@ public void testTemplateIfWithElse() {
 				</body>
 				</html>
 				 	 """).
-					condition("aCondition", true)));
+					condition("aCondition", true).
+					condition("bCondition", false)));
 	}
 	
 	@Test
@@ -781,7 +783,8 @@ public void testTemplateNestedIf() {
 				</body>
 				</html>
 				 	 """).
-					condition("aCondition", true)));
+					condition("aCondition", true).
+					condition("bCondition", false)));
 		
 	}
 	
@@ -801,36 +804,6 @@ public void testTEMPYYYY() {
 		
 	}
 	
-	@Test
-	public void testTEMPXXXXXXX() {
-		Assertions.assertEquals("""
-				<html>
-				<body>
-				
-				<p>Show this</p>
-				
-				<p>And show this too</p>
-				
-				
-				</body>
-				</html>
-				""", 
-				createParser().process(TemplateModel.ofContent("""
-				<html>
-				<body>
-				<t:if aCondition>
-				<p>Show this</p>
-				<t:if !bCondition>
-				<p>And show this too</p>
-				</t:if>
-				</t:if>
-				</body>
-				</html>
-				 	 """).
-					condition("aCondition", true)));
-		
-	}
-	
 	@Test
 	public void testTemplateNestedIf2() {
 		Assertions.assertEquals("""