Get-PermissionLevelMapping

# Connect to the source and destination sites
$srcSite = Connect-Site -Url "http://myfarm1/sites/mysourcesite"
$dstSite = Connect-Site -Url "http://myfarm1/sites/mydestinationsite"

# Retrieve and display the current permission level mappings
$mappingSettings = Get-PermissionLevelMapping -SourceSite $srcSite -DestinationSite $dstSite
$mappingSettings

# Output:
# PropertyMappings        :
# ContentTypeMappings     :
# UserAndGroupMappings    :
# PermissionLevelMappings : Approve              -> Approve
#                           Contribute           -> Contribute
#                           Design               -> Design
#                           Full Control         -> Full Control
#                           My Custom Permission -> <NO DESTINATION>
#                           Read                 -> Read
#                           View Only            -> View Only
# SiteTemplateMappings    :

# Connect to the destination site
$dstSite = Connect-Site -Url "http://myfarm1/sites/mydestinationsite"

# Retrieve permission level mappings from the file system and apply them to the destination site
$mappingSettings = Get-PermissionLevelMapping -FromFileSystem -DestinationSite $dstSite

# Display the retrieved permission level mappings
$mappingSettings
# Output:
# PropertyMappings        :
# ContentTypeMappings     :
# UserAndGroupMappings    :
# PermissionLevelMappings : Full Control   -> Full Control
#                           Modify         -> Contribute
#                           Read & execute -> Read
#                           Read           -> Read
#                           Write          -> Contribute
# SiteTemplateMappings    :

# Map "My Custom Permission" to "Full Control"
$mappingSettings = Set-PermissionLevelMapping -Source "My Custom Permission" -Destination "Full Control"

# Connect to the source and destination sites
$srcSite = Connect-Site -Url "http://myfarm1/sites/mysourcesite"
$dstSite = Connect-Site -Url "http://myfarm1/sites/mydestinationsite"

# Retrieve and display the updated permission level mappings, with site context
$mappingSettings = Get-PermissionLevelMapping -MappingSettings $mappingSettings -SourceSite $srcSite -DestinationSite $dstSite
$mappingSettings
# Output:
# PropertyMappings        :
# ContentTypeMappings     :
# UserAndGroupMappings    :
# PermissionLevelMappings : Approve              -> Approve
#                           Contribute           -> Contribute
#                           Design               -> Design
#                           Full Control         -> Full Control
#                           My Custom Permission -> Full Control
#                           Read                 -> <NO DESTINATION>
#                           View Only            -> View Only
# SiteTemplateMappings    :

Get-PermissionLevelMapping-SourceSite <Site>
-DestinationSite <Site>
[-MappingSettings <MappingSettings>]

Get-PermissionLevelMapping-FromFileSystem <SwitchParameter>
-DestinationSite <Site>
[-MappingSettings <MappingSettings>]