diff --git a/DESCRIPTION b/DESCRIPTION
index c096001..1e3a4a8 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -14,7 +14,7 @@ Depends:
     R (>= 3.3)
 Imports:
     AzureAuth,
-    AzureGraph (>= 1.2.1),
+    AzureGraph (>= 1.2.2),
     utils,
     curl,
     httr,
diff --git a/NEWS.md b/NEWS.md
index 047dca3..89aaa43 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,3 +1,9 @@
+# Microsoft365R 2.1.0.9000
+
+- Add `list_members()` and `get_member()` methods for teams and channels.
+- Add support for @mentions in Teams channel messages (#26).
+- Add a `by_item` argument to the `delete_item()` method for drives and the `delete()` method for drive items. This is to allow deletion of non-empty folders on SharePoint sites with data protection policies in place. Use with caution (#21).
+
 # Microsoft365R 2.1.0
 
 - Add support for sending and managing emails in Outlook. Use the `get_personal_outlook()` and `get_business_outlook()` client functions to access the emails in your personal account and work or school account, respectively. Functionality supported includes:
diff --git a/R/Microsoft365R.R b/R/Microsoft365R.R
index b310d1a..595e683 100644
--- a/R/Microsoft365R.R
+++ b/R/Microsoft365R.R
@@ -49,8 +49,9 @@ utils::globalVariables(c("self", "private"))
 # CLI for Microsoft 365 app ID
 .cli_microsoft365_app_id <- "31359c7f-bd7e-475c-86db-fdb8c937548e"
 
-# helper function
+# helper functions
 error_message <- get("error_message", getNamespace("AzureGraph"))
+get_confirmation <- get("get_confirmation", getNamespace("AzureGraph"))
 
 # dummy mention to keep CRAN happy
 # we need to ensure that vctrs is loaded so that AzureGraph will use vec_rbind
diff --git a/R/ms_drive.R b/R/ms_drive.R
index 2d7f032..9a43f2e 100644
--- a/R/ms_drive.R
+++ b/R/ms_drive.R
@@ -20,7 +20,7 @@
 #' - `create_folder(path)`: Create a folder.
 #' - `open_item(path)`: Open a file or folder.
 #' - `create_share_link(...)`: Create a shareable link for a file or folder.
-#' - `delete_item(path, confirm)`: Delete a file or folder.
+#' - `delete_item(path, confirm, by_item)`: Delete a file or folder. By default, ask for confirmation first. For personal OneDrive, deleting a folder will also automatically delete its contents; for business OneDrive or SharePoint document libraries, you may need to set `by_item=TRUE` to delete the contents first depending on your organisation's policies. Note that this can be slow for large folders.
 #' - `get_item(path)`: Get an item representing a file or folder.
 #' - `get_item_properties(path)`: Get the properties (metadata) for a file or folder.
 #' - `set_item_properties(path, ...)`: Set the properties for a file or folder.
@@ -134,9 +134,9 @@ public=list(
         self$get_item(path)$open()
     },
 
-    delete_item=function(path, confirm=TRUE)
+    delete_item=function(path, confirm=TRUE, by_item=FALSE)
     {
-        self$get_item(path)$delete(confirm=confirm)
+        self$get_item(path)$delete(confirm=confirm, by_item=by_item)
     },
 
     get_item=function(path)
diff --git a/R/ms_drive_item.R b/R/ms_drive_item.R
index 97770f9..182eaee 100644
--- a/R/ms_drive_item.R
+++ b/R/ms_drive_item.R
@@ -10,7 +10,7 @@
 #' - `properties`: The item properties (metadata).
 #' @section Methods:
 #' - `new(...)`: Initialize a new object. Do not call this directly; see 'Initialization' below.
-#' - `delete(confirm=TRUE)`: Delete this item. By default, ask for confirmation first. For personal OneDrives, deleting a folder will also automatically delete its contents; for business OneDrives or SharePoint document libraries, you must delete the folder contents first before deleting the folder.
+#' - `delete(confirm=TRUE, by_item=FALSE)`: Delete this item. By default, ask for confirmation first. For personal OneDrive, deleting a folder will also automatically delete its contents; for business OneDrive or SharePoint document libraries, you may need to set `by_item=TRUE` to delete the contents first depending on your organisation's policies. Note that this can be slow for large folders.
 #' - `update(...)`: Update the item's properties (metadata) in Microsoft Graph.
 #' - `do_operation(...)`: Carry out an arbitrary operation on the item.
 #' - `sync_fields()`: Synchronise the R object with the item metadata in Microsoft Graph.
@@ -109,6 +109,40 @@ public=list(
         super$initialize(token, tenant, properties)
     },
 
+    delete=function(confirm=TRUE, by_item=FALSE)
+    {
+        if(!by_item || !self$is_folder())
+            return(super$delete(confirm=confirm))
+
+        if (confirm && interactive())
+        {
+            msg <- sprintf("Do you really want to delete the %s '%s'?", self$type, self$properties$name)
+            if (!get_confirmation(msg, FALSE))
+                return(invisible(NULL))
+        }
+
+        children <- self$list_items()
+        dirs <- children$isdir
+        for(d in children$name[dirs])
+            self$get_item(d)$delete(confirm=FALSE, by_item=TRUE)
+
+        deletes <- lapply(children$name[!dirs], function(f)
+        {
+            path <- private$make_absolute_path(f)
+            graph_request$new(path, http_verb="DELETE")
+        })
+        # do in batches of 20
+        i <- length(deletes)
+        while(i > 0)
+        {
+            batch <- seq(from=max(1, i - 19), to=i)
+            call_batch_endpoint(self$token, deletes[batch])
+            i <- max(1, i - 19) - 1
+        }
+
+        super$delete(confirm=FALSE)
+    },
+
     is_folder=function()
     {
         !is.null(self$properties$folder)
diff --git a/man/ms_drive.Rd b/man/ms_drive.Rd
index 9c1dec1..104e000 100644
--- a/man/ms_drive.Rd
+++ b/man/ms_drive.Rd
@@ -34,7 +34,7 @@ Class representing a personal OneDrive or SharePoint document library.
 \item \code{create_folder(path)}: Create a folder.
 \item \code{open_item(path)}: Open a file or folder.
 \item \code{create_share_link(...)}: Create a shareable link for a file or folder.
-\item \code{delete_item(path, confirm)}: Delete a file or folder.
+\item \code{delete_item(path, confirm, by_item)}: Delete a file or folder. By default, ask for confirmation first. For personal OneDrive, deleting a folder will also automatically delete its contents; for business OneDrive or SharePoint document libraries, you may need to set \code{by_item=TRUE} to delete the contents first depending on your organisation's policies. Note that this can be slow for large folders.
 \item \code{get_item(path)}: Get an item representing a file or folder.
 \item \code{get_item_properties(path)}: Get the properties (metadata) for a file or folder.
 \item \code{set_item_properties(path, ...)}: Set the properties for a file or folder.
diff --git a/man/ms_drive_item.Rd b/man/ms_drive_item.Rd
index e863f42..aa397b4 100644
--- a/man/ms_drive_item.Rd
+++ b/man/ms_drive_item.Rd
@@ -24,7 +24,7 @@ Class representing an item (file or folder) in a OneDrive or SharePoint document
 
 \itemize{
 \item \code{new(...)}: Initialize a new object. Do not call this directly; see 'Initialization' below.
-\item \code{delete(confirm=TRUE)}: Delete this item. By default, ask for confirmation first. For personal OneDrives, deleting a folder will also automatically delete its contents; for business OneDrives or SharePoint document libraries, you must delete the folder contents first before deleting the folder.
+\item \code{delete(confirm=TRUE, by_item=FALSE)}: Delete this item. By default, ask for confirmation first. For personal OneDrive, deleting a folder will also automatically delete its contents; for business OneDrive or SharePoint document libraries, you may need to set \code{by_item=TRUE} to delete the contents first depending on your organisation's policies. Note that this can be slow for large folders.
 \item \code{update(...)}: Update the item's properties (metadata) in Microsoft Graph.
 \item \code{do_operation(...)}: Carry out an arbitrary operation on the item.
 \item \code{sync_fields()}: Synchronise the R object with the item metadata in Microsoft Graph.
diff --git a/tests/testthat/test01_onedrive.R b/tests/testthat/test01_onedrive.R
index 8ff5353..076a10a 100644
--- a/tests/testthat/test01_onedrive.R
+++ b/tests/testthat/test01_onedrive.R
@@ -130,7 +130,7 @@ test_that("Methods work with filenames with special characters",
 })
 
 
-test_that("Nested folder creation works",
+test_that("Nested folder creation/deletion works",
 {
     od <- get_personal_onedrive()
 
@@ -144,8 +144,10 @@ test_that("Nested folder creation works",
     it1 <- od$get_item(f1)
     expect_is(it1, "ms_drive_item")
 
+    replicate(30, it1$upload(write_file()))
+
     it123 <- it1$create_folder(file.path(f2, f3))
     expect_is(it123, "ms_drive_item")
 
-    expect_silent(it1$delete(confirm=FALSE))
+    expect_silent(it1$delete(confirm=FALSE, by_item=TRUE))
 })
diff --git a/tests/testthat/test02_business_onedrive.R b/tests/testthat/test02_business_onedrive.R
index c49de76..f234969 100644
--- a/tests/testthat/test02_business_onedrive.R
+++ b/tests/testthat/test02_business_onedrive.R
@@ -145,7 +145,7 @@ test_that("Methods work with filenames with special characters",
 })
 
 
-test_that("Nested folder creation works",
+test_that("Nested folder creation/deletion works",
 {
     od <- get_business_onedrive()
 
@@ -159,10 +159,10 @@ test_that("Nested folder creation works",
     it1 <- od$get_item(f1)
     expect_is(it1, "ms_drive_item")
 
+    replicate(30, it1$upload(write_file()))
+
     it123 <- it1$create_folder(file.path(f2, f3))
     expect_is(it123, "ms_drive_item")
 
-    expect_silent(it123$delete(confirm=FALSE))
-    expect_silent(it12$delete(confirm=FALSE))
-    expect_silent(it1$delete(confirm=FALSE))
+    expect_silent(it1$delete(confirm=FALSE, by_item=TRUE))
 })