diff --git a/DocFx.ps1 b/DocFx.ps1
index e69de29..7d35d91 100644
--- a/DocFx.ps1
+++ b/DocFx.ps1
@@ -0,0 +1,83 @@
+# Copyright (c) Microsoft Corporation.
+# Licensed under the MIT License.
+
+function Start-DocFx
+{
+    <#
+    .SYNOPSIS
+        Start docfx in current folder or $env:DefaultDocFxPath.
+        Reuse existing docfx instance already running if possible.
+
+    .PARAMETER Force
+        Don't reuse anything and don't use defaults.
+        Just open a new docfx in the current folder.
+
+    .EXAMPLE
+        Start-DocFx
+
+        Tries to reopen a currently opened docfx.
+    #>
+
+    [Diagnostics.CodeAnalysis.SuppressMessageAttribute(
+        'PSUseShouldProcessForStateChangingFunctions', '',
+        Justification = 'Intended to be this way')]
+    param
+    (
+        [switch] $Force
+    )
+
+    # Test if docfx is installed
+    if( -not (Get-Command docfx.exe -ea Ignore) )
+    {
+        throw "docfx.exe must be discoverable via PATH environment variable"
+    }
+
+    # Cleanup cleanup jobs =)
+    $cleanupJobName = "Start-DocFx cleanup"
+    Get-Job $cleanupJobName -ea Ignore | where State -eq Completed | Remove-Job
+
+    # Helper function
+    function Open-DocFx( $folder = $pwd )
+    {
+        $path = Get-ChildItem -Recurse docfx.json | select -First 1
+        $ps = Start-Process `
+            -FilePath "pwsh" `
+            -ArgumentList ('-Command "docfx ' + $path + ' --serve"') `
+            -WorkingDirectory $folder `
+            -WindowStyle Hidden `
+            -PassThru
+
+        Start-Job -Name $cleanupJobName {
+            Start-Sleep -Seconds 60
+            $ps | Stop-Process
+        } | Out-Null
+    }
+
+    # When need to open new docfx in current folder
+    if( $Force )
+    {
+        "Open new docfx in current folder $pwd"
+        Open-DocFx
+        return
+    }
+
+    # Trying to reuse opened docfx if possible
+    if( Get-Process docfx -ea Ignore )
+    {
+        "Found existing docfx, reopening default URL"
+        Start-Process http://localhost:8080
+        return
+    }
+
+    # Run notebook from default location if possible
+    if( $env:DefaultDocFxPath )
+    {
+        "Open new docfx in `$env:DefaultDocFxPath = $env:DefaultDocFxPath"
+        Open-DocFx $env:DefaultDocFxPath
+    }
+    else
+    {
+        "Open new docfx in current folder $pwd, note that you can use `$env:DefaultDocFxPath instead if you define it"
+        Open-DocFx
+    }
+}
\ No newline at end of file
diff --git a/PSToolset.psd1 b/PSToolset.psd1
index 9ede80e..9100e2f 100644
--- a/PSToolset.psd1
+++ b/PSToolset.psd1
@@ -64,6 +64,7 @@
         "Get-Parameter", "Use-Project", "Use-Filter",
         "Get-Ini", "Show-Ini", "ConvertFrom-Ini", "Import-Ini",
         # DoxFx
+        "Start-DocFx",
         # Files
         "Resolve-ScriptPath", "Get-FileEncoding",
         # Functional
diff --git a/PSToolset.psm1 b/PSToolset.psm1
index 20d790e..dabe858 100644
--- a/PSToolset.psm1
+++ b/PSToolset.psm1
@@ -30,6 +30,7 @@ Set-Alias any       Test-Any
 Set-Alias call      Set-CmdEnvironment
 Set-Alias construct ConvertTo-PsObject
 Set-Alias default   Use-Default
+Set-Alias dfx       Start-DocFx
 Set-Alias first     Get-First
 Set-Alias f         Use-Filter
 Set-Alias gite      Open-GitExtensions
diff --git a/Python.ps1 b/Python.ps1
index 1de3a28..65f6081 100644
--- a/Python.ps1
+++ b/Python.ps1
@@ -6,7 +6,7 @@ function Start-JupyterNotebook
     <#
     .SYNOPSIS
         Start Jupyter Notebook in current folder or $env:DefaultJupyterNotebookPath.
-        Reuse existing notebook already running if possible
+        Reuse existing notebook already running if possible.
 
     .PARAMETER Force
         Don't reuse anything and don't use defaults.