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diff --git a/src/main/java/org/apache/commons/math3/stat/interval/AgrestiCoullInterval.java b/src/main/java/org/apache/commons/math3/stat/interval/AgrestiCoullInterval.java
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+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.commons.math3.stat.interval;
+
+import org.apache.commons.math3.distribution.NormalDistribution;
+import org.apache.commons.math3.util.FastMath;
+
+/**
+ * Implements the Agresti-Coull method for creating a binomial proportion confidence interval.
+ *
+ * @see <a
+ *      href="http://en.wikipedia.org/wiki/Binomial_proportion_confidence_interval#Agresti-Coull_Interval">
+ *      Agresti-Coull interval (Wikipedia)</a>
+ * @since 3.3
+ */
+public class AgrestiCoullInterval implements BinomialConfidenceInterval {
+
+    /** {@inheritDoc} */
+    public ConfidenceInterval createInterval(int numberOfTrials, int numberOfSuccesses, double confidenceLevel) {
+        IntervalUtils.checkParameters(numberOfTrials, numberOfSuccesses, confidenceLevel);
+        final double alpha = (1.0 - confidenceLevel) / 2;
+        final NormalDistribution normalDistribution = new NormalDistribution();
+        final double z = normalDistribution.inverseCumulativeProbability(1 - alpha);
+        final double zSquared = FastMath.pow(z, 2);
+        final double modifiedNumberOfTrials = numberOfTrials + zSquared;
+        final double modifiedSuccessesRatio = (1.0 / modifiedNumberOfTrials) * (numberOfSuccesses + 0.5 * zSquared);
+        final double difference = z *
+                                  FastMath.sqrt(1.0 / modifiedNumberOfTrials * modifiedSuccessesRatio *
+                                                (1 - modifiedSuccessesRatio));
+        return new ConfidenceInterval(modifiedSuccessesRatio - difference, modifiedSuccessesRatio + difference,
+                                      confidenceLevel);
+    }
+
+}