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diff --git a/subprojects/viatra-runtime-localsearch/src/main/java/tools/refinery/viatra/runtime/localsearch/planner/cost/impl/VariableBindingBasedCostFunction.java b/subprojects/viatra-runtime-localsearch/src/main/java/tools/refinery/viatra/runtime/localsearch/planner/cost/impl/VariableBindingBasedCostFunction.java
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+/*******************************************************************************
+ * Copyright (c) 2010-2014, Marton Bur, Balazs Grill, Akos Horvath, Zoltan Ujhelyi, Istvan Rath and Daniel Varro
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-v20.html.
+ * 
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package tools.refinery.viatra.runtime.localsearch.planner.cost.impl;
+
+import java.util.Set;
+
+import tools.refinery.viatra.runtime.localsearch.planner.cost.IConstraintEvaluationContext;
+import tools.refinery.viatra.runtime.localsearch.planner.cost.ICostFunction;
+import tools.refinery.viatra.runtime.matchers.psystem.PConstraint;
+import tools.refinery.viatra.runtime.matchers.psystem.PVariable;
+import tools.refinery.viatra.runtime.matchers.psystem.basicdeferred.AggregatorConstraint;
+import tools.refinery.viatra.runtime.matchers.psystem.basicdeferred.ExportedParameter;
+import tools.refinery.viatra.runtime.matchers.psystem.basicdeferred.NegativePatternCall;
+import tools.refinery.viatra.runtime.matchers.psystem.basicenumerables.BinaryTransitiveClosure;
+import tools.refinery.viatra.runtime.matchers.psystem.basicenumerables.ConstantValue;
+
+/**
+ * This class can be used to calculate cost of application of a constraint with a given adornment.
+ * 
+ * For now the logic is based on the following principles:
+ * 
+ * <li>The transitive closures, NACs and count finds are the most expensive operations
+ * 
+ * <li>The number of free variables increase the cost
+ * 
+ * <li>If all the variables of a constraint are free, then its cost equals to twice the number of its parameter
+ * variables. This solves the problem of unnecessary iteration over instances at the beginning of a plan (thus causing
+ * very long run times when executing the plan) by applying constraints based on structural features as soon as
+ * possible.
+ * 
+ * <br>
+ * 
+ * @author Marton Bur
+ * @since 1.4
+ *
+ */
+public class VariableBindingBasedCostFunction implements ICostFunction {
+
+    // Static cost definitions
+    private static int MAX = 1000;
+    private static int exportedParameterCost = MAX - 20;
+    private static int binaryTransitiveClosureCost = MAX - 50;
+    private static int nacCost = MAX - 100;
+    private static int aggregatorCost = MAX - 200;
+    private static int constantCost = 0;
+    
+    @Override
+    public double apply(IConstraintEvaluationContext input) {
+        PConstraint constraint = input.getConstraint();
+        Set<PVariable> affectedVariables = constraint.getAffectedVariables();
+
+        int cost = 0;
+
+        // For constants the cost is determined to be 0.0
+        // The following constraints should be checks:
+        // * Binary transitive closure
+        // * NAC
+        // * count
+        // * exported parameter - only a metadata
+        if (constraint instanceof ConstantValue) {
+            cost = constantCost;
+        } else if (constraint instanceof BinaryTransitiveClosure) {
+            cost = binaryTransitiveClosureCost;
+        } else if (constraint instanceof NegativePatternCall) {
+            cost = nacCost;
+        } else if (constraint instanceof AggregatorConstraint) {
+            cost = aggregatorCost;
+        } else if (constraint instanceof ExportedParameter) {
+            cost = exportedParameterCost;
+        } else {
+            // In case of other constraints count the number of unbound variables
+            for (PVariable pVariable : affectedVariables) {
+                if (input.getFreeVariables().contains(pVariable)) {
+                    // For each free variable ('without-value-variable') increase cost
+                    cost += 1;
+                }
+            }
+            if (cost == affectedVariables.size()) {
+                // If all the variables are free, double the cost.
+                // This ensures that iteration costs more
+                cost *= 2;
+            }
+
+        }
+
+        return Float.valueOf(cost);
+    }
+
+}