diff --git a/.gitignore b/.gitignore
index 39c909fa..e1a85a64 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,6 +5,7 @@ upload-docs.*.log.json
 /.vscode/
 /.idea/
 /.settings/
+/json_docs/
 *.swp
 coverage
 .nyc_output
diff --git a/src/fn/merge-contacts.js b/src/fn/merge-contacts.js
new file mode 100644
index 00000000..963ae6aa
--- /dev/null
+++ b/src/fn/merge-contacts.js
@@ -0,0 +1,200 @@
+const minimist = require('minimist');
+const path = require('path');
+
+const environment = require('../lib/environment');
+const lineageManipulation = require('../lib/lineage-manipulation');
+const lineageConstraints = require('../lib/lineage-constraints');
+const pouch = require('../lib/db');
+const { trace, info } = require('../lib/log');
+
+const {
+  BATCH_SIZE,
+  prepareDocumentDirectory,
+  prettyPrintDocument,
+  replaceLineageInAncestors,
+  bold,
+  writeDocumentToDisk,
+  fetch,
+} = require('../lib/mm-shared');
+
+module.exports = {
+  requiresInstance: true,
+  execute: () => {
+    const args = parseExtraArgs(environment.pathToProject, environment.extraArgs);
+    const db = pouch();
+    prepareDocumentDirectory(args);
+    return updateLineagesAndStage(args, db);
+  }
+};
+
+const updateLineagesAndStage = async (options, db) => {
+  trace(`Fetching contact details: ${options.winnerId}`);
+  const winnerDoc = await fetch.contact(db, options.winnerId);
+
+  const constraints = await lineageConstraints(db, winnerDoc);
+  const loserDocs = await fetch.contactList(db, options.loserIds);
+  await validateContacts(loserDocs, constraints);
+
+  let affectedContactCount = 0, affectedReportCount = 0;
+  const replacementLineage = lineageManipulation.createLineageFromDoc(winnerDoc);
+  for (let loserId of options.loserIds) {
+    const contactDoc = loserDocs[loserId];
+    const descendantsAndSelf = await fetch.descendantsOf(db, loserId);
+
+    const self = descendantsAndSelf.find(d => d._id === loserId);
+    writeDocumentToDisk(options, {
+      _id: self._id,
+      _rev: self._rev,
+      _deleted: true,
+    });
+
+    // Check that primary contact is not removed from areas where they are required
+    const invalidPrimaryContactDoc = await constraints.getPrimaryContactViolations(contactDoc, descendantsAndSelf);
+    if (invalidPrimaryContactDoc) {
+      throw Error(`Cannot remove contact ${prettyPrintDocument(invalidPrimaryContactDoc)} from the hierarchy for which they are a primary contact.`);
+    }
+
+    trace(`Considering lineage updates to ${descendantsAndSelf.length} descendant(s) of contact ${prettyPrintDocument(contactDoc)}.`);
+    const updatedDescendants = replaceLineageInContacts(descendantsAndSelf, replacementLineage, loserId);
+
+    const ancestors = await fetch.ancestorsOf(db, contactDoc);
+    trace(`Considering primary contact updates to ${ancestors.length} ancestor(s) of contact ${prettyPrintDocument(contactDoc)}.`);
+    const updatedAncestors = replaceLineageInAncestors(descendantsAndSelf, ancestors);
+
+    minifyLineageAndWriteToDisk([...updatedDescendants, ...updatedAncestors], options);
+
+    const movedReportsCount = await moveReports(db, descendantsAndSelf, options, options.winnerId, loserId);
+    trace(`${movedReportsCount} report(s) created by these affected contact(s) will be updated`);
+
+    affectedContactCount += updatedDescendants.length + updatedAncestors.length;
+    affectedReportCount += movedReportsCount;
+
+    info(`Staged updates to ${prettyPrintDocument(contactDoc)}. ${updatedDescendants.length} contact(s) and ${movedReportsCount} report(s).`);
+  }
+
+  info(`Staged changes to lineage information for ${affectedContactCount} contact(s) and ${affectedReportCount} report(s).`);
+};
+
+/*
+Checks for any errors which this will create in the hierarchy (hierarchy schema, circular hierarchies)
+Confirms the list of contacts are possible to move
+*/
+const validateContacts = async (contactDocs, constraints) => {
+  Object.values(contactDocs).forEach(doc => {
+    const hierarchyError = constraints.getHierarchyErrors(doc);
+    if (hierarchyError) {
+      throw Error(`Hierarchy Constraints: ${hierarchyError}`);
+    }
+  });
+
+  /*
+  It is nice that the tool can move lists of contacts as one operation, but strange things happen when two loserIds are in the same lineage.
+  For example, moving a district_hospital and moving a contact under that district_hospital to a new clinic causes multiple colliding writes to the same json file.
+  */
+  const loserIds = Object.keys(contactDocs);
+  Object.values(contactDocs)
+    .forEach(doc => {
+      const parentIdsOfDoc = (doc.parent && lineageManipulation.pluckIdsFromLineage(doc.parent)) || [];
+      const violatingParentId = parentIdsOfDoc.find(winnerId => loserIds.includes(winnerId));
+      if (violatingParentId) {
+        throw Error(`Unable to move two documents from the same lineage: '${doc._id}' and '${violatingParentId}'`);
+      }
+    });
+};
+
+// Parses extraArgs and asserts if required parameters are not present
+const parseExtraArgs = (projectDir, extraArgs = []) => {
+  const args = minimist(extraArgs, { boolean: true });
+
+  const loserIds = (args.losers || args.loser || '')
+    .split(',')
+    .filter(Boolean);
+
+  if (loserIds.length === 0) {
+    usage();
+    throw Error(`Action "merge-contacts" is missing required list of contacts ${bold('--losers')} to be merged into the winner`);
+  }
+
+  if (!args.winner) {
+    usage();
+    throw Error(`Action "merge-contacts" is missing required parameter ${bold('--winner')}`);
+  }
+
+  return {
+    winnerId: args.winner,
+    loserIds,
+    docDirectoryPath: path.resolve(projectDir, args.docDirectoryPath || 'json_docs'),
+    force: !!args.force,
+  };
+};
+
+const usage = () => {
+  info(`
+${bold('cht-conf\'s merge-contacts action')}
+When combined with 'upload-docs' this action merges multiple contacts and all their associated data into one.
+
+${bold('USAGE')}
+cht --local merge-contacts -- --winner=<winner_id> --losers=<loser_id1>,<loser_id2>
+
+${bold('OPTIONS')}
+--winner=<winner_id>
+  Specifies the ID of the contact that should have all other contact data merged into it.
+
+--losers=<loser_id1>,<loser_id2>
+  A comma delimited list of IDs of contacts which will be deleted and all of their data will be merged into the winner contact.
+
+--docDirectoryPath=<path to stage docs>
+  Specifies the folder used to store the documents representing the changes in hierarchy.
+`);
+};
+
+const moveReports = async (db, descendantsAndSelf, writeOptions, winnerId, loserId) => {
+  let skip = 0;
+  let reportDocsBatch;
+  do {
+    info(`Processing ${skip} to ${skip + BATCH_SIZE} report docs`);
+    reportDocsBatch = await fetch.reportsCreatedFor(db, loserId, skip);
+
+    reportDocsBatch.forEach(report => {
+      const subjectIds = ['patient_id', 'patient_uuid', 'place_id', 'place_uuid'];
+      for (const subjectId of subjectIds) {
+        if (report[subjectId]) {
+          report[subjectId] = winnerId;
+        } 
+
+        if (report.fields[subjectId]) {
+          report.fields[subjectId] = winnerId;
+        }
+      }
+
+      writeDocumentToDisk(writeOptions, report);
+    });
+
+    skip += reportDocsBatch.length;
+  } while (reportDocsBatch.length >= BATCH_SIZE);
+
+  return skip;
+};
+
+const minifyLineageAndWriteToDisk = (docs, parsedArgs) => {
+  docs.forEach(doc => {
+    lineageManipulation.minifyLineagesInDoc(doc);
+    writeDocumentToDisk(parsedArgs, doc);
+  });
+};
+
+const replaceLineageInContacts = (descendantsAndSelf, replacementLineage, contactId) => descendantsAndSelf.reduce((agg, doc) => {
+  // skip top-level because it is now being deleted
+  if (doc._id === contactId) {
+    return agg;
+  }
+
+  const parentWasUpdated = lineageManipulation.replaceLineage(doc, 'parent', replacementLineage, contactId);
+
+  // TODO: seems wrong
+  const contactWasUpdated = lineageManipulation.replaceLineage(doc, 'contact', replacementLineage, contactId);
+  if (parentWasUpdated || contactWasUpdated) {
+    agg.push(doc);
+  }
+  return agg;
+}, []);
diff --git a/src/fn/move-contacts.js b/src/fn/move-contacts.js
index 6b29e3b0..e0c9ff24 100644
--- a/src/fn/move-contacts.js
+++ b/src/fn/move-contacts.js
@@ -1,16 +1,21 @@
 const minimist = require('minimist');
 const path = require('path');
-const userPrompt = require('../lib/user-prompt');
 
 const environment = require('../lib/environment');
-const fs = require('../lib/sync-fs');
 const lineageManipulation = require('../lib/lineage-manipulation');
 const lineageConstraints = require('../lib/lineage-constraints');
 const pouch = require('../lib/db');
-const { warn, trace, info } = require('../lib/log');
-
-const HIERARCHY_ROOT = 'root';
-const BATCH_SIZE = 10000;
+const { trace, info } = require('../lib/log');
+
+const {
+  HIERARCHY_ROOT,
+  BATCH_SIZE,
+  prepareDocumentDirectory,
+  prettyPrintDocument, 
+  replaceLineageInAncestors,
+  bold,
+  fetch,
+} = require('../lib/mm-shared');
 
 module.exports = {
   requiresInstance: true,
@@ -22,7 +27,6 @@ module.exports = {
   }
 };
 
-const prettyPrintDocument = doc => `'${doc.name}' (${doc._id})`;
 const updateLineagesAndStage = async (options, db) => {
   trace(`Fetching contact details for parent: ${options.parentId}`);
   const parentDoc = await fetch.contact(db, options.parentId);
@@ -117,21 +121,7 @@ const parseExtraArgs = (projectDir, extraArgs = []) => {
   };
 };
 
-const prepareDocumentDirectory = ({ docDirectoryPath, force }) => {
-  if (!fs.exists(docDirectoryPath)) {
-    fs.mkdir(docDirectoryPath);
-  } else if (!force && fs.recurseFiles(docDirectoryPath).length > 0) {
-    warn(`The document folder '${docDirectoryPath}' already contains files. It is recommended you start with a clean folder. Do you want to delete the contents of this folder and continue?`);
-    if(userPrompt.keyInYN()) {
-      fs.deleteFilesInFolder(docDirectoryPath);
-    } else {
-      throw new Error('User aborted execution.');
-    }
-  }
-};
-
 const usage = () => {
-  const bold = text => `\x1b[1m${text}\x1b[0m`;
   info(`
 ${bold('cht-conf\'s move-contacts action')}
 When combined with 'upload-docs' this action effectively moves a contact from one place in the hierarchy to another.
@@ -176,92 +166,6 @@ const minifyLineageAndWriteToDisk = (docs, parsedArgs) => {
   });
 };
 
-const writeDocumentToDisk = ({ docDirectoryPath }, doc) => {
-  const destinationPath = path.join(docDirectoryPath, `${doc._id}.doc.json`);
-  if (fs.exists(destinationPath)) {
-    warn(`File at ${destinationPath} already exists and is being overwritten.`);
-  }
-
-  trace(`Writing updated document to ${destinationPath}`);
-  fs.writeJson(destinationPath, doc);
-};
-
-const fetch = {
-  /*
-  Fetches all of the documents associated with the "contactIds" and confirms they exist.
-  */
-  contactList: async (db, ids) => {
-    const contactDocs = await db.allDocs({
-      keys: ids,
-      include_docs: true,
-    });
-
-    const missingContactErrors = contactDocs.rows.filter(row => !row.doc).map(row => `Contact with id '${row.key}' could not be found.`);
-    if (missingContactErrors.length > 0) {
-      throw Error(missingContactErrors);
-    }
-
-    return contactDocs.rows.reduce((agg, curr) => Object.assign(agg, { [curr.doc._id]: curr.doc }), {});
-  },
-
-  contact: async (db, id) => {
-    try {
-      if (id === HIERARCHY_ROOT) {
-        return undefined;
-      }
-
-      return await db.get(id);
-    } catch (err) {
-      if (err.name !== 'not_found') {
-        throw err;
-      }
-
-      throw Error(`Contact with id '${id}' could not be found`);
-    }
-  },
-
-  /*
-  Given a contact's id, obtain the documents of all descendant contacts
-  */
-  descendantsOf: async (db, contactId) => {
-    const descendantDocs = await db.query('medic/contacts_by_depth', {
-      key: [contactId],
-      include_docs: true,
-    });
-
-    return descendantDocs.rows
-      .map(row => row.doc)
-      /* We should not move or update tombstone documents */
-      .filter(doc => doc && doc.type !== 'tombstone');
-  },
-
-  reportsCreatedBy: async (db, contactIds, skip) => {
-    const reports = await db.query('medic-client/reports_by_freetext', {
-      keys: contactIds.map(id => [`contact:${id}`]),
-      include_docs: true,
-      limit: BATCH_SIZE,
-      skip: skip,
-    });
-
-    return reports.rows.map(row => row.doc);
-  },
-
-  ancestorsOf: async (db, contactDoc) => {
-    const ancestorIds = lineageManipulation.pluckIdsFromLineage(contactDoc.parent);
-    const ancestors = await db.allDocs({
-      keys: ancestorIds,
-      include_docs: true,
-    });
-
-    const ancestorIdsNotFound = ancestors.rows.filter(ancestor => !ancestor.doc).map(ancestor => ancestor.key);
-    if (ancestorIdsNotFound.length > 0) {
-      throw Error(`Contact '${prettyPrintDocument(contactDoc)} has parent id(s) '${ancestorIdsNotFound.join(',')}' which could not be found.`);
-    }
-
-    return ancestors.rows.map(ancestor => ancestor.doc);
-  },
-};
-
 const replaceLineageInReports = (reportsCreatedByDescendants, replaceWith, startingFromIdInLineage) => reportsCreatedByDescendants.reduce((agg, doc) => {
   if (lineageManipulation.replaceLineage(doc, 'contact', replaceWith, startingFromIdInLineage)) {
     agg.push(doc);
@@ -278,14 +182,3 @@ const replaceLineageInContacts = (descendantsAndSelf, replacementLineage, contac
   }
   return agg;
 }, []);
-
-const replaceLineageInAncestors = (descendantsAndSelf, ancestors) => ancestors.reduce((agg, ancestor) => {
-  let result = agg;
-  const primaryContact = descendantsAndSelf.find(descendant => ancestor.contact && descendant._id === ancestor.contact._id);
-  if (primaryContact) {
-    ancestor.contact = lineageManipulation.createLineageFromDoc(primaryContact);
-    result = [ancestor, ...result];
-  }
-
-  return result;
-}, []);
diff --git a/src/lib/mm-shared.js b/src/lib/mm-shared.js
new file mode 100644
index 00000000..bd324a13
--- /dev/null
+++ b/src/lib/mm-shared.js
@@ -0,0 +1,153 @@
+const path = require('path');
+
+const userPrompt = require('./user-prompt');
+const fs = require('./sync-fs');
+const { warn, trace } = require('./log');
+const lineageManipulation = require('./lineage-manipulation');
+
+const HIERARCHY_ROOT = 'root';
+const BATCH_SIZE = 10000;
+
+const prettyPrintDocument = doc => `'${doc.name}' (${doc._id})`;
+
+const prepareDocumentDirectory = ({ docDirectoryPath, force }) => {
+  if (!fs.exists(docDirectoryPath)) {
+    fs.mkdir(docDirectoryPath);
+  } else if (!force && fs.recurseFiles(docDirectoryPath).length > 0) {
+    warn(`The document folder '${docDirectoryPath}' already contains files. It is recommended you start with a clean folder. Do you want to delete the contents of this folder and continue?`);
+    if(userPrompt.keyInYN()) {
+      fs.deleteFilesInFolder(docDirectoryPath);
+    } else {
+      throw new Error('User aborted execution.');
+    }
+  }
+};
+
+const writeDocumentToDisk = ({ docDirectoryPath }, doc) => {
+  const destinationPath = path.join(docDirectoryPath, `${doc._id}.doc.json`);
+  if (fs.exists(destinationPath)) {
+    warn(`File at ${destinationPath} already exists and is being overwritten.`);
+  }
+
+  trace(`Writing updated document to ${destinationPath}`);
+  fs.writeJson(destinationPath, doc);
+};
+
+const replaceLineageInAncestors = (descendantsAndSelf, ancestors) => ancestors.reduce((agg, ancestor) => {
+  let result = agg;
+  const primaryContact = descendantsAndSelf.find(descendant => ancestor.contact && descendant._id === ancestor.contact._id);
+  if (primaryContact) {
+    ancestor.contact = lineageManipulation.createLineageFromDoc(primaryContact);
+    result = [ancestor, ...result];
+  }
+
+  return result;
+}, []);
+
+
+const fetch = {
+  /*
+  Fetches all of the documents associated with the "contactIds" and confirms they exist.
+  */
+  contactList: async (db, ids) => {
+    const contactDocs = await db.allDocs({
+      keys: ids,
+      include_docs: true,
+    });
+
+    const missingContactErrors = contactDocs.rows.filter(row => !row.doc).map(row => `Contact with id '${row.key}' could not be found.`);
+    if (missingContactErrors.length > 0) {
+      throw Error(missingContactErrors);
+    }
+
+    return contactDocs.rows.reduce((agg, curr) => Object.assign(agg, { [curr.doc._id]: curr.doc }), {});
+  },
+
+  contact: async (db, id) => {
+    try {
+      if (id === HIERARCHY_ROOT) {
+        return undefined;
+      }
+
+      return await db.get(id);
+    } catch (err) {
+      if (err.name !== 'not_found') {
+        throw err;
+      }
+
+      throw Error(`Contact with id '${id}' could not be found`);
+    }
+  },
+
+  /*
+  Given a contact's id, obtain the documents of all descendant contacts
+  */
+  descendantsOf: async (db, contactId) => {
+    const descendantDocs = await db.query('medic/contacts_by_depth', {
+      key: [contactId],
+      include_docs: true,
+    });
+
+    return descendantDocs.rows
+      .map(row => row.doc)
+      /* We should not move or update tombstone documents */
+      .filter(doc => doc && doc.type !== 'tombstone');
+  },
+
+  reportsCreatedBy: async (db, contactIds, skip) => {
+    const reports = await db.query('medic-client/reports_by_freetext', {
+      keys: contactIds.map(id => [`contact:${id}`]),
+      include_docs: true,
+      limit: BATCH_SIZE,
+      skip,
+    });
+
+    return reports.rows.map(row => row.doc);
+  },
+
+  reportsCreatedFor: async (db, contactId, skip) => {
+    // TODO is this the right way?
+    const reports = await db.query('medic-client/reports_by_freetext', {
+      keys: [
+        [`patient_id:${contactId}`],
+        [`patient_uuid:${contactId}`],
+        [`place_id:${contactId}`],
+        [`place_uuid:${contactId}`],
+      ],
+      include_docs: true,
+      limit: BATCH_SIZE,
+      skip,
+    });
+
+    return reports.rows.map(row => row.doc);
+  },
+
+  ancestorsOf: async (db, contactDoc) => {
+    const ancestorIds = lineageManipulation.pluckIdsFromLineage(contactDoc.parent);
+    const ancestors = await db.allDocs({
+      keys: ancestorIds,
+      include_docs: true,
+    });
+
+    const ancestorIdsNotFound = ancestors.rows.filter(ancestor => !ancestor.doc).map(ancestor => ancestor.key);
+    if (ancestorIdsNotFound.length > 0) {
+      throw Error(`Contact '${prettyPrintDocument(contactDoc)} has parent id(s) '${ancestorIdsNotFound.join(',')}' which could not be found.`);
+    }
+
+    return ancestors.rows.map(ancestor => ancestor.doc);
+  },
+};
+
+const bold = text => `\x1b[1m${text}\x1b[0m`;
+
+module.exports = {
+  HIERARCHY_ROOT,
+  BATCH_SIZE,
+  bold,
+  prepareDocumentDirectory,
+  prettyPrintDocument,
+  minifyLineageAndWriteToDisk, 
+  replaceLineageInAncestors,
+  writeDocumentToDisk,
+  fetch,
+};