diff --git a/smnp/ast/node/expression.py b/smnp/ast/node/expression.py
index 70fa201..40fc7e7 100644
--- a/smnp/ast/node/expression.py
+++ b/smnp/ast/node/expression.py
@@ -14,6 +14,14 @@ ExpressionParser = Parser.leftAssociativeOperatorParser(TermParser, [TokenType.P
 Expression2Parser = Parser.leftAssociativeOperatorParser(ExpressionParser, [TokenType.RELATION], ExpressionParser,
                                                          lambda left, op, right: Expression.withValue(BinaryOperator.withValues(left, op, right)))
 
+Expression3Parser = Parser.leftAssociativeOperatorParser(Expression2Parser, [TokenType.AND], Expression2Parser,
+                                                         lambda left, op, right: Expression.withValue(BinaryOperator.withValues(left, op, right)))
+
+Expression4Parser = Parser.leftAssociativeOperatorParser(Expression3Parser, [TokenType.OR], Expression3Parser,
+                                                         lambda left, op, right: Expression.withValue(BinaryOperator.withValues(left, op, right)))
+
+MaxPrecedenceExpressionParser = Expression4Parser
+
 #
 # class ExpressionNode(Node):
 #     def __init__(self, pos):
diff --git a/smnp/ast/node/program.py b/smnp/ast/node/program.py
index 31dae96..157cf1b 100644
--- a/smnp/ast/node/program.py
+++ b/smnp/ast/node/program.py
@@ -1,4 +1,4 @@
-from smnp.ast.node.expression import Expression2Parser
+from smnp.ast.node.expression import MaxPrecedenceExpressionParser
 from smnp.ast.node.model import Node, ParseResult
 from smnp.ast.parser import Parser
 
@@ -15,7 +15,7 @@ def parse(input):
 
 
             #TODO -> temporary (to remove):
-            Expression2Parser
+            MaxPrecedenceExpressionParser
         )(input)
 
         if result.result:
diff --git a/smnp/token/tokenizer.py b/smnp/token/tokenizer.py
index 4969a07..9abaa06 100644
--- a/smnp/token/tokenizer.py
+++ b/smnp/token/tokenizer.py
@@ -49,7 +49,10 @@ tokenizers = (
     separated(defaultTokenizer(TokenType.EXTEND)),
     separated(defaultTokenizer(TokenType.IMPORT)),
     separated(defaultTokenizer(TokenType.FROM)),
+    separated(defaultTokenizer(TokenType.AND)),
+    separated(defaultTokenizer(TokenType.NOT)),
     separated(defaultTokenizer(TokenType.AS)),
+    separated(defaultTokenizer(TokenType.OR)),
 
     # Identifier (couldn't be before keywords!)
     identifierTokenizer,
diff --git a/smnp/token/type.py b/smnp/token/type.py
index 749bd1c..0beb508 100644
--- a/smnp/token/type.py
+++ b/smnp/token/type.py
@@ -22,6 +22,9 @@ class TokenType(Enum):
     DOTS = '...'
     AMP = '&'
     DOT = '.'
+    AND = 'and'
+    OR = 'or'
+    NOT = 'not'
     INTEGER = 'integer'
     STRING = 'string'
     NOTE = 'note'