diff --git a/java/src/org/broadinstitute/sting/gatk/dataSources/shards/AdaptiveShard.java b/java/src/org/broadinstitute/sting/gatk/dataSources/shards/AdaptiveShard.java
new file mode 100644
index 000000000..90180f02a
--- /dev/null
+++ b/java/src/org/broadinstitute/sting/gatk/dataSources/shards/AdaptiveShard.java
@@ -0,0 +1,58 @@
+package org.broadinstitute.sting.gatk.dataSources.shards;
+
+import net.sf.samtools.SAMSequenceDictionary;
+
+/**
+ *
+ * User: aaron
+ * Date: Apr 6, 2009
+ * Time: 7:18:19 PM
+ *
+ * The Broad Institute
+ * SOFTWARE COPYRIGHT NOTICE AGREEMENT 
+ * This software and its documentation are copyright 2009 by the
+ * Broad Institute/Massachusetts Institute of Technology. All rights are reserved.
+ *
+ * This software is supplied without any warranty or guaranteed support whatsoever. Neither
+ * the Broad Institute nor MIT can be responsible for its use, misuse, or functionality.
+ *
+ */
+
+
+/**
+ * @author aaron
+ * @version 1.0
+ * @date Apr 6, 2009
+ * <p/>
+ * Class AdaptiveShard
+ * <p/>
+ * A descriptions should go here. Blame aaron if it's missing.
+ */
+class AdaptiveShard extends Shard {
+
+    // default the next size to 100,000
+    private long nextShardSize = 100000;
+
+    /**
+     * the constructor, taking a seq dictionary to parse out contigs
+     *
+     * @param dic the seq dictionary
+     */
+    AdaptiveShard(SAMSequenceDictionary dic, long startSize) {
+        super(dic);
+        this.nextShardSize = startSize;
+    }
+
+    public void setNextShardSize(long size) {
+        nextShardSize = size;
+    }
+
+    /**
+     * This is how the various shards strategies implements their approach
+     *
+     * @return the next shard size
+     */
+    protected long nextShardSize() {
+        return nextShardSize;
+    }
+}
diff --git a/java/src/org/broadinstitute/sting/gatk/dataSources/shards/LinearShard.java b/java/src/org/broadinstitute/sting/gatk/dataSources/shards/LinearShard.java
new file mode 100644
index 000000000..8287ea51f
--- /dev/null
+++ b/java/src/org/broadinstitute/sting/gatk/dataSources/shards/LinearShard.java
@@ -0,0 +1,54 @@
+package org.broadinstitute.sting.gatk.dataSources.shards;
+
+import net.sf.samtools.SAMSequenceDictionary;
+
+/**
+ *
+ * User: aaron
+ * Date: Apr 6, 2009
+ * Time: 8:23:19 PM
+ *
+ * The Broad Institute
+ * SOFTWARE COPYRIGHT NOTICE AGREEMENT 
+ * This software and its documentation are copyright 2009 by the
+ * Broad Institute/Massachusetts Institute of Technology. All rights are reserved.
+ *
+ * This software is supplied without any warranty or guaranteed support whatsoever. Neither
+ * the Broad Institute nor MIT can be responsible for its use, misuse, or functionality.
+ *
+ */
+
+
+/**
+ * @author aaron
+ * @version 1.0
+ * @date Apr 6, 2009
+ * <p/>
+ * Class LinearShard
+ * <p/>
+ * A descriptions should go here. Blame aaron if it's missing.
+ */
+public class LinearShard extends Shard {
+
+    // fixed size
+    private long nextShardSize = 100000;
+
+    /**
+     * the constructor, taking a seq dictionary to parse out contigs
+     *
+     * @param dic the seq dictionary
+     */
+    LinearShard(SAMSequenceDictionary dic, long startSize) {
+        super(dic);
+        this.nextShardSize = startSize;
+    }
+
+    /**
+     * This is how the various shards strategies implements their approach
+     *
+     * @return the next shard size
+     */
+    protected long nextShardSize() {
+        return nextShardSize;
+    }
+}
diff --git a/java/src/org/broadinstitute/sting/gatk/dataSources/shards/Shard.java b/java/src/org/broadinstitute/sting/gatk/dataSources/shards/Shard.java
new file mode 100644
index 000000000..9eeb3241c
--- /dev/null
+++ b/java/src/org/broadinstitute/sting/gatk/dataSources/shards/Shard.java
@@ -0,0 +1,126 @@
+package org.broadinstitute.sting.gatk.dataSources.shards;
+
+import net.sf.samtools.SAMSequenceDictionary;
+import org.broadinstitute.sting.utils.GenomeLoc;
+
+import java.util.Iterator;
+/**
+ *
+ * User: aaron
+ * Date: Apr 6, 2009
+ * Time: 11:23:17 AM
+ *
+ * The Broad Institute
+ * SOFTWARE COPYRIGHT NOTICE AGREEMENT 
+ * This software and its documentation are copyright 2009 by the
+ * Broad Institute/Massachusetts Institute of Technology. All rights are reserved.
+ *
+ * This software is supplied without any warranty or guaranteed support whatsoever. Neither
+ * the Broad Institute nor MIT can be responsible for its use, misuse, or functionality.
+ *
+ */
+
+/**
+ * @author aaron
+ * @version 1.0
+ * @date Apr 6, 2009
+ * <p/>
+ * Interface Shard
+ * <p/>
+ * The shard interface, which controls how data is divided
+ */
+public abstract class Shard implements Iterator<GenomeLoc> {
+
+    // this stores the seq dictionary, which is a reference for the
+    // lengths and names of contigs, which you need to generate an iterative stratagy
+    protected static SAMSequenceDictionary dic = null;
+
+    // the current genome location
+    protected GenomeLoc mLoc = null;
+
+    // current seq location
+    protected int seqLoc = 0;
+
+    // the actual last size; this can change based on contig endings
+    protected long lastGenomeLocSize = 0;
+
+    // do we have another contig?
+    private boolean nextContig = false;
+
+
+    /**
+     * the constructor, taking a seq dictionary to parse out contigs
+     *
+     * @param dic the seq dictionary
+     */
+    Shard(SAMSequenceDictionary dic) {
+        this.dic = dic;
+        mLoc = new GenomeLoc(dic.getSequence(0).getSequenceName(), 0, 0);
+        if (dic.getSequences().size() > 0) {
+            nextContig = true;
+        }
+    }
+
+
+    /**
+     * This is how the various shards strategies implements their approach
+     *
+     * @return the next shard size
+     */
+    protected abstract long nextShardSize();
+
+    /**
+     * get the next shard, based on the return size of nextShardSize
+     *
+     * @return
+     */
+    public GenomeLoc next() {
+        // lets get some background info on the problem
+        long length = dic.getSequence(seqLoc).getSequenceLength();
+        long proposedSize = nextShardSize();
+        long nextStart = mLoc.getStop() + 1;
+        // can we fit it into the current seq size?
+        if (nextStart + proposedSize < length) {
+            lastGenomeLocSize = proposedSize;
+            mLoc = new GenomeLoc(dic.getSequence(seqLoc).getSequenceName(), nextStart, nextStart + proposedSize);
+            return new GenomeLoc(dic.getSequence(seqLoc).getSequenceName(), nextStart, nextStart + proposedSize);
+        }
+        // else we can't make it in the current location, we have to stitch one together
+        else {
+            lastGenomeLocSize = nextStart + proposedSize - length;
+
+
+            // move to the next contig
+            jumpContig();
+            return new GenomeLoc(dic.getSequence(seqLoc).getSequenceName(), nextStart, lastGenomeLocSize);
+        }
+
+    }
+
+    /** jump to the next contig */
+    private void jumpContig() {
+        ++seqLoc;
+        if (dic.getSequences().size() <= seqLoc) {
+            nextContig = false;
+            return;
+        }
+
+        // the next sequence should start at the begining of the next contig
+        mLoc = new GenomeLoc(dic.getSequence(seqLoc).getSequenceName(), 0, 0);
+
+    }
+
+    /**
+     * is there another GenomeLoc to get?
+     *
+     * @return
+     */
+    public boolean hasNext() {
+        return nextContig;
+    }
+
+    /** we don't support remove */
+    public void remove() {
+        throw new UnsupportedOperationException("Can not remove records from a shard iterator!");
+    }
+}
diff --git a/java/src/org/broadinstitute/sting/gatk/dataSources/shards/ShardFactory.java b/java/src/org/broadinstitute/sting/gatk/dataSources/shards/ShardFactory.java
new file mode 100644
index 000000000..04ff96b3a
--- /dev/null
+++ b/java/src/org/broadinstitute/sting/gatk/dataSources/shards/ShardFactory.java
@@ -0,0 +1,66 @@
+package org.broadinstitute.sting.gatk.dataSources.shards;
+
+import net.sf.samtools.SAMSequenceDictionary;
+
+/**
+ *
+ * User: aaron
+ * Date: Apr 6, 2009
+ * Time: 7:09:22 PM
+ *
+ * The Broad Institute
+ * SOFTWARE COPYRIGHT NOTICE AGREEMENT 
+ * This software and its documentation are copyright 2009 by the
+ * Broad Institute/Massachusetts Institute of Technology. All rights are reserved.
+ *
+ * This software is supplied without any warranty or guaranteed support whatsoever. Neither
+ * the Broad Institute nor MIT can be responsible for its use, misuse, or functionality.
+ *
+ */
+
+
+/**
+ * @author aaron
+ * @version 1.0
+ * @date Apr 6, 2009
+ * <p/>
+ * Class ShardBuilder
+ * <p/>
+ * A descriptions should go here. Blame aaron if it's missing.
+ */
+public class ShardFactory {
+    public enum SHATTER_STRATEGY {
+        ADAPTIVE, LINEAR
+    }
+
+    /**
+     * get a new shatter strategy
+     *
+     * @param strat        what's our strategy - SHATTER_STRATEGY type
+     * @param dic          the seq dictionary
+     * @param startingSize the starting size
+     * @return
+     */
+    static public Shard shatter(SHATTER_STRATEGY strat, SAMSequenceDictionary dic, long startingSize) {
+        Shard d = null;
+        switch (strat) {
+            case ADAPTIVE:
+                d = new AdaptiveShard(dic, startingSize);
+            default:
+                d = new LinearShard(dic, startingSize); // default
+        }
+        return d;
+    }
+
+    /**
+     * if you know what you want
+     *
+     * @param dic          the seq dictionary
+     * @param startingSize the starting size
+     * @return
+     */
+    static public AdaptiveShard getAdaptiveShard(SAMSequenceDictionary dic, long startingSize) {
+        return new AdaptiveShard(dic, startingSize);
+    }
+
+}