diff --git a/engine-extensions/src/main/java/io/nosqlbench/engine/extensions/computefunctions/ComputeFunctions.java b/engine-extensions/src/main/java/io/nosqlbench/engine/extensions/computefunctions/ComputeFunctions.java
index 44c8cd0f0..94d26d9f7 100644
--- a/engine-extensions/src/main/java/io/nosqlbench/engine/extensions/computefunctions/ComputeFunctions.java
+++ b/engine-extensions/src/main/java/io/nosqlbench/engine/extensions/computefunctions/ComputeFunctions.java
@@ -189,4 +189,33 @@ public class ComputeFunctions {
         return 2.0d * ((recallAtK * precisionAtK) / (recallAtK + precisionAtK));
     }
 
+    /**
+     * Reciprocal Rank - The multiplicative inverse of the first rank which is relevant.
+     */
+    public static double RR(long[] reference, long[] sample, int limit) {
+        int firstRank = Intersections.firstMatchingIndex(reference, sample, limit);
+        if (firstRank >= 0) {
+            return 1.0d / (firstRank+1);
+        } else {
+            return 0.0;
+        }
+    }
+
+    public static double RR(long[] reference, long[] sample) {
+        return RR(reference, sample, reference.length);
+    }
+
+    public static double RR(int[] reference, int[] sample, int limit) {
+        int firstRank = Intersections.firstMatchingIndex(reference, sample, limit);
+        if (firstRank >= 0) {
+            return 1.0d / (firstRank+1);
+        } else {
+            return 0.0;
+        }
+    }
+
+    public static double RR(int[] reference, int[] sample) {
+        return RR(reference, sample, reference.length);
+    }
+
 }
diff --git a/engine-extensions/src/main/java/io/nosqlbench/engine/extensions/computefunctions/Intersections.java b/engine-extensions/src/main/java/io/nosqlbench/engine/extensions/computefunctions/Intersections.java
index 97fe5699b..290cb4419 100644
--- a/engine-extensions/src/main/java/io/nosqlbench/engine/extensions/computefunctions/Intersections.java
+++ b/engine-extensions/src/main/java/io/nosqlbench/engine/extensions/computefunctions/Intersections.java
@@ -20,6 +20,32 @@ import java.util.Arrays;
 
 public class Intersections {
 
+    /**
+     * Return a non-negative index of the first value in the sample array which is present in the reference array,
+     * OR, return a negative number. This returns array index which start at 0, not rank, which is starts at 1.
+     */
+    public static int firstMatchingIndex(long[] reference, long[] sample, int limit) {
+        Arrays.sort(reference);
+        int maxIndex = Math.min(sample.length, limit);
+        int foundAt=-1;
+        for (int index = 0; index < maxIndex; index++) {
+            foundAt = Arrays.binarySearch(reference, sample[index]);
+            if (foundAt>=0) break;
+        }
+        return foundAt;
+    }
+
+    public static int firstMatchingIndex(int[] reference, int[] sample, int limit) {
+        Arrays.sort(reference);
+        int maxIndex = Math.min(sample.length, limit);
+        int foundAt=-1;
+        for (int index = 0; index < maxIndex; index++) {
+            foundAt = Arrays.binarySearch(reference, sample[index]);
+            if (foundAt>=0) break;
+        }
+        return foundAt;
+    }
+
     public static int count(int[] reference, int[] sample) {
         return count(reference,sample,reference.length);
     }
diff --git a/engine-extensions/src/test/java/io/nosqlbench/engine/extensions/computefunctions/ComputeFunctionsTest.java b/engine-extensions/src/test/java/io/nosqlbench/engine/extensions/computefunctions/ComputeFunctionsTest.java
index 15d7700e7..546b5d911 100644
--- a/engine-extensions/src/test/java/io/nosqlbench/engine/extensions/computefunctions/ComputeFunctionsTest.java
+++ b/engine-extensions/src/test/java/io/nosqlbench/engine/extensions/computefunctions/ComputeFunctionsTest.java
@@ -78,4 +78,15 @@ class ComputeFunctionsTest {
         }
 
     }
+
+    @Test
+    public void testReciprocalRank() {
+        assertThat(ComputeFunctions.RR(intsBy3_369,highInts56789))
+            .as("relevant results in rank 2 should yield RR=0.5")
+            .isCloseTo(0.5d,offset);
+
+        assertThat(ComputeFunctions.RR(highInts56789,lowInts01234))
+            .as("no relevant results should yield RR=0.0")
+            .isCloseTo(0.0d,offset);
+    }
 }