diff --git a/azure-pipelines.yml b/azure-pipelines.yml
index fd4f5c9212..7c6791ae76 100644
--- a/azure-pipelines.yml
+++ b/azure-pipelines.yml
@@ -78,6 +78,23 @@ stages:
         npm install tslint --verbose
         npm run lint
       displayName: Run Lint
+  ##### Verify NPM and Yarn are in sync #####
+  - job: SyncPackageManagers
+    displayName: 'Verify NPM & Yarn In-Sync [Local Copy of Target Branch Must Be Up to Date]'
+    pool:
+      vmImage: 'windows-latest'
+    steps:
+    - task: UsePythonVersion@0
+      inputs:
+        versionSpec: '3.x'
+        addToPath: true
+        architecture: 'x64'
+    - task: PythonScript@0
+      inputs:
+        scriptSource: 'filePath'
+        scriptPath: 'dependency-verifier.py'
+        arguments: '$(System.PullRequest.TargetBranch)'
+        failOnStderr: true  
   ##### Package and Publish #####
   - job: Package
     displayName: 'Package and Publish'
diff --git a/dependency-verifier.py b/dependency-verifier.py
new file mode 100644
index 0000000000..8f058c53c5
--- /dev/null
+++ b/dependency-verifier.py
@@ -0,0 +1,85 @@
+import sys
+import subprocess
+import os
+from pathlib import Path
+
+
+def main():
+    """Check if the dependency updates in package-lock are also updated in yarn.locks"""
+    targetBranch = sys.argv[1] # Script is called with PR Target Branch Name, Fulfilled by AzDo
+    subprocess.getoutput(f"git fetch --all")
+    subprocess.getoutput(f"git pull origin {targetBranch}")
+    VerifyDependencies(targetBranch)
+    sys.exit(0)
+
+def VerifyDependencies(targetBranch):
+    """Enumerate through all changed files to check diffs."""
+    # origin/ requires origin/ to be up to date. 
+    changedFiles = [Path(path) for path in subprocess.getoutput(f"git diff --name-only origin/{targetBranch}..").splitlines()]
+    npmLockFile = "package-lock.json"
+    
+    for file in changedFiles:
+        fileName = os.path.basename(os.path.realpath(file))
+        if fileName == npmLockFile:
+            NpmChangesMirrorYarnChanges(changedFiles, file, targetBranch)
+
+def GetNpmDependencyUpdates(packageLockDiffLines):
+    """Returns a dictionary of [dependency -> [] (can be changed to version in later implementations)] changes found in diff string of package-lock.json"""
+    # Assumes dependency line starts with "node_modules/DEPENDENCYNAME". Version may or may not come after
+    dependencies = {}
+    for line in packageLockDiffLines:
+        line = line.strip()
+        line = line.lstrip("\t")
+        if line.startswith('"node_modules/'):
+            dependencies[line.split('"node_modules/', 1)[1].split('"', 1)[0]] = [] # will be "node_modules/dep further" content, need to cull
+    return dependencies
+
+def GetYarnDependencyUpdates(yarnLockDiffLines):
+    """Returns a dictionary of [dependency -> [] (can be changed to version in later implementations)] changes found in diff string of yarn.lock"""
+    # Assumes dependency line starts with DEPEDENCY@Version without whitespace
+    dependencies = {}
+    for line in yarnLockDiffLines:
+        if line == line.lstrip() and "@" in line:
+            depsAtVers = line.lstrip('"').split(",") # multiple dependencies are possible with diff versions, sep by ,
+            for dependencyAtVers in depsAtVers:
+                dep = dependencyAtVers.rsplit("@", 1)[0]
+                vers = dependencyAtVers.rsplit("@", 1)[1]
+                dependencies[dep] = [] # Could add version here later. (TODO) that will probably not happen
+    return dependencies
+
+def GetUnmatchedDiffs(yarnDiff, npmDiff):
+    """Returns [] if dependency updates are reflected in both diffs, elsewise the dependencies out of sync."""
+                                        # v Remove + or - from diff and additional git diff context lines
+    yarnDeps = GetYarnDependencyUpdates([line[1:] for line in yarnDiff.splitlines() if line.startswith("+") or line.startswith("-")])
+    npmDeps = GetNpmDependencyUpdates([line[1:] for line in npmDiff.splitlines() if line.startswith("+") or line.startswith("-")])
+    outOfSyncDependencies = []
+    for dep in npmDeps:
+        if dep in yarnDeps and yarnDeps[dep] == npmDeps[dep]: # version changes match
+            continue
+        else:
+            outOfSyncDependencies.append(dep)
+    return outOfSyncDependencies
+
+def NpmChangesMirrorYarnChanges(changedFiles, packageLockPath, targetBranch):
+    """Returns successfully if yarn.lock matches packagelock changes, if not, throws exit code"""
+    yarnLockFile = "yarn.lock"
+    yarnLockPath = Path(os.path.join(os.path.dirname(packageLockPath), yarnLockFile))
+    outOfDateYarnLocks = []
+    
+    if yarnLockPath in changedFiles:
+        yarnDiff = subprocess.getoutput(f"git diff origin/{targetBranch}.. -- {str(yarnLockPath)}")
+        npmDiff = subprocess.getoutput(f"git diff origin/{targetBranch}..  -- {packageLockPath}")
+        diffSetComplement = GetUnmatchedDiffs(yarnDiff, npmDiff)
+        if diffSetComplement == []:
+           pass
+        else:
+            outOfDateYarnLocks.append((str(yarnLockPath), diffSetComplement))
+    else:
+        outOfDateYarnLocks.append(yarnLockPath)
+    if(outOfDateYarnLocks != []):
+        sys.exit(f"The yarn.lock and package-lock appear to be out of sync with the changes made after {targetBranch}. Update by doing yarn import or yarn add dep@package-lock-version for {outOfDateYarnLocks}. For sub-dependencies, try adding just the main dependency first.")
+    else:
+        return 0 # OK, status here is not used
+    
+if __name__ == "__main__":
+    main()
\ No newline at end of file