diff --git a/Dockerfile b/Dockerfile
index 9d6b96fb..1b36d0d9 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -22,6 +22,7 @@ RUN apt-get update && apt-get install -y \
     protobuf-c-compiler \
     protobuf-compiler \
     python-minimal \
+    uidmap \
     --no-install-recommends \
     && apt-get clean
 
diff --git a/tests/integration/exec.bats b/tests/integration/exec.bats
index 70730de8..8d943aab 100644
--- a/tests/integration/exec.bats
+++ b/tests/integration/exec.bats
@@ -100,8 +100,8 @@ function teardown() {
 }
 
 @test "runc exec --user" {
-  # --user can't work in rootless containers
-  requires root
+  # --user can't work in rootless containers that don't have idmap.
+  [[ "$ROOTLESS" -ne 0 ]] && requires rootless_idmap
 
   # run busybox detached
   runc run -d --console-socket $CONSOLE_SOCKET test_busybox
@@ -110,5 +110,5 @@ function teardown() {
   runc exec --user 1000:1000 test_busybox id
   [ "$status" -eq 0 ]
 
-  [[ ${output} == "uid=1000 gid=1000" ]]
+  [[ "${output}" == "uid=1000 gid=1000"* ]]
 }
diff --git a/tests/integration/helpers.bash b/tests/integration/helpers.bash
index 29e0fef6..e44fcaa7 100644
--- a/tests/integration/helpers.bash
+++ b/tests/integration/helpers.bash
@@ -58,15 +58,41 @@ function __runc() {
 	"$RUNC" --log /proc/self/fd/2 --root "$ROOT" "$@"
 }
 
-# Wrapper for runc spec.
+# Wrapper for runc spec, which takes only one argument (the bundle path).
 function runc_spec() {
-	local args=""
+	! [[ "$#" > 1 ]]
+
+	local args=()
+	local bundle=""
 
 	if [ "$ROOTLESS" -ne 0 ]; then
-		args+="--rootless"
+		args+=("--rootless")
+	fi
+	if [ "$#" -ne 0 ]; then
+		bundle="$1"
+		args+=("--bundle" "$bundle")
 	fi
 
-	runc spec $args "$@"
+	runc spec "${args[@]}"
+
+	# Always add additional mappings if we have idmaps.
+	if [[ "$ROOTLESS" -ne 0 ]] && [[ "$ROOTLESS_FEATURES" == *"idmap"* ]]; then
+		runc_rootless_idmap "$bundle"
+	fi
+}
+
+# Shortcut to add additional uids and gids, based on the values set as part of
+# a rootless configuration.
+function runc_rootless_idmap() {
+	bundle="${1:-.}"
+	cat "$bundle/config.json" \
+		| jq '.mounts |= map((select(.type == "devpts") | .options += ["gid=5"]) // .)' \
+		| jq '.linux.uidMappings |= .+ [{"hostID": '"$ROOTLESS_UIDMAP_START"', "containerID": 1000, "size": '"$ROOTLESS_UIDMAP_LENGTH"'}]' \
+		| jq '.linux.gidMappings |= .+ [{"hostID": '"$ROOTLESS_GIDMAP_START"', "containerID": 100, "size": 1}]' \
+		| jq '.linux.gidMappings |= .+ [{"hostID": '"$(($ROOTLESS_GIDMAP_START+10))"', "containerID": 1, "size": 20}]' \
+		| jq '.linux.gidMappings |= .+ [{"hostID": '"$(($ROOTLESS_GIDMAP_START+100))"', "containerID": 1000, "size": '"$(($ROOTLESS_GIDMAP_LENGTH-1000))"'}]' \
+		>"$bundle/config.json.tmp"
+	mv "$bundle/config.json"{.tmp,}
 }
 
 # Fails the current test, providing the error given.
@@ -90,14 +116,19 @@ function requires() {
 				skip "test requires ${var}"
 			fi
 			;;
+		rootless_idmap)
+			if [[ "$ROOTLESS_FEATURES" != *"idmap"* ]]; then
+				skip "test requires ${var}"
+			fi
+			;;
 		cgroups_kmem)
 			if [ ! -e "$KMEM" ]; then
-				skip "Test requires ${var}."
+				skip "Test requires ${var}"
 			fi
 			;;
 		cgroups_rt)
 			if [ ! -e "$RT_PERIOD" ]; then
-				skip "Test requires ${var}."
+				skip "Test requires ${var}"
 			fi
 			;;
 		*)
diff --git a/tests/integration/spec.bats b/tests/integration/spec.bats
index 60617060..c9ba2aaa 100644
--- a/tests/integration/spec.bats
+++ b/tests/integration/spec.bats
@@ -51,7 +51,7 @@ function teardown() {
   [ ! -e "$HELLO_BUNDLE"/config.json ]
 
   # test generation of spec does not return an error
-  runc_spec --bundle "$HELLO_BUNDLE"
+  runc_spec "$HELLO_BUNDLE"
   [ "$status" -eq 0 ]
 
   # test generation of spec created our config.json (spec)
diff --git a/tests/integration/start_detached.bats b/tests/integration/start_detached.bats
index 0dc5e0d8..7f177b86 100644
--- a/tests/integration/start_detached.bats
+++ b/tests/integration/start_detached.bats
@@ -21,8 +21,8 @@ function teardown() {
 }
 
 @test "runc run detached ({u,g}id != 0)" {
-  # cannot start containers as another user in rootless setup
-  requires root
+  # cannot start containers as another user in rootless setup without idmap
+  [[ "$ROOTLESS" -ne 0 ]] && requires rootless_idmap
 
   # replace "uid": 0 with "uid": 1000
   # and do a similar thing for gid.
diff --git a/tests/integration/start_hello.bats b/tests/integration/start_hello.bats
index 2e935728..a706be27 100644
--- a/tests/integration/start_hello.bats
+++ b/tests/integration/start_hello.bats
@@ -21,8 +21,8 @@ function teardown() {
 }
 
 @test "runc run ({u,g}id != 0)" {
-  # cannot start containers as another user in rootless setup
-  requires root
+  # cannot start containers as another user in rootless setup without idmap
+  [[ "$ROOTLESS" -ne 0 ]] && requires rootless_idmap
 
   # replace "uid": 0 with "uid": 1000
   # and do a similar thing for gid.
diff --git a/tests/integration/tty.bats b/tests/integration/tty.bats
index 985a9b75..a59652bb 100644
--- a/tests/integration/tty.bats
+++ b/tests/integration/tty.bats
@@ -24,9 +24,9 @@ function teardown() {
 }
 
 @test "runc run [tty owner]" {
-	# tty chmod is not doable in rootless containers.
+	# tty chmod is not doable in rootless containers without idmap.
 	# TODO: this can be made as a change to the gid test.
-	requires root
+	[[ "$ROOTLESS" -ne 0 ]] && requires rootless_idmap
 
 	# Replace sh script with stat.
 	sed -i 's/"sh"/"sh", "-c", "stat -c %u:%g $(tty) | tr : \\\\\\\\n"/' config.json
@@ -40,8 +40,8 @@ function teardown() {
 }
 
 @test "runc run [tty owner] ({u,g}id != 0)" {
-	# tty chmod is not doable in rootless containers.
-	requires root
+	# tty chmod is not doable in rootless containers without idmap.
+	[[ "$ROOTLESS" -ne 0 ]] && requires rootless_idmap
 
 	# replace "uid": 0 with "uid": 1000
 	# and do a similar thing for gid.
@@ -76,9 +76,9 @@ function teardown() {
 }
 
 @test "runc exec [tty owner]" {
-	# tty chmod is not doable in rootless containers.
+	# tty chmod is not doable in rootless containers without idmap.
 	# TODO: this can be made as a change to the gid test.
-	requires root
+	[[ "$ROOTLESS" -ne 0 ]] && requires rootless_idmap
 
 	# run busybox detached
 	runc run -d --console-socket $CONSOLE_SOCKET test_busybox
@@ -95,8 +95,8 @@ function teardown() {
 }
 
 @test "runc exec [tty owner] ({u,g}id != 0)" {
-	# tty chmod is not doable in rootless containers.
-	requires root
+	# tty chmod is not doable in rootless containers without idmap.
+	[[ "$ROOTLESS" -ne 0 ]] && requires rootless_idmap
 
 	# replace "uid": 0 with "uid": 1000
 	# and do a similar thing for gid.
diff --git a/tests/rootless.sh b/tests/rootless.sh
index 2613c702..cb2c0647 100755
--- a/tests/rootless.sh
+++ b/tests/rootless.sh
@@ -19,9 +19,42 @@
 # a new feature, please match the existing style. Add an entry to $ALL_FEATURES,
 # and add an enable_* and disable_* hook.
 
-ALL_FEATURES=()
+ALL_FEATURES=("idmap")
 ROOT="$(readlink -f "$(dirname "${BASH_SOURCE}")/..")"
 
+# FEATURE: Opportunistic new{uid,gid}map support, allowing a rootless container
+#          to be set up with the usage of helper setuid binaries.
+
+function enable_idmap() {
+	export ROOTLESS_UIDMAP_START=100000 ROOTLESS_UIDMAP_LENGTH=65536
+	export ROOTLESS_GIDMAP_START=200000 ROOTLESS_GIDMAP_LENGTH=65536
+
+	# Set up sub{uid,gid} mappings.
+	[ -e /etc/subuid.tmp ] && mv /etc/subuid{.tmp,}
+	( grep -v '^rootless' /etc/subuid ; echo "rootless:$ROOTLESS_UIDMAP_START:$ROOTLESS_UIDMAP_LENGTH" ) > /etc/subuid.tmp
+	mv /etc/subuid{.tmp,}
+	[ -e /etc/subgid.tmp ] && mv /etc/subgid{.tmp,}
+	( grep -v '^rootless' /etc/subgid ; echo "rootless:$ROOTLESS_GIDMAP_START:$ROOTLESS_GIDMAP_LENGTH" ) > /etc/subgid.tmp
+	mv /etc/subgid{.tmp,}
+
+	# Reactivate new{uid,gid}map helpers if applicable.
+	[ -e /usr/bin/unused-newuidmap ] && mv /usr/bin/{unused-,}newuidmap
+	[ -e /usr/bin/unused-newgidmap ] && mv /usr/bin/{unused-,}newgidmap
+}
+
+function disable_idmap() {
+	export ROOTLESS_UIDMAP_START ROOTLESS_UIDMAP_LENGTH
+	export ROOTLESS_GIDMAP_START ROOTLESS_GIDMAP_LENGTH
+
+	# Deactivate sub{uid,gid} mappings.
+	[ -e /etc/subuid ] && mv /etc/subuid{,.tmp}
+	[ -e /etc/subgid ] && mv /etc/subgid{,.tmp}
+
+	# Deactivate new{uid,gid}map helpers. setuid is preserved with mv(1).
+	[ -e /usr/bin/newuidmap ] && mv /usr/bin/{,unused-}newuidmap
+	[ -e /usr/bin/newgidmap ] && mv /usr/bin/{,unused-}newgidmap
+}
+
 # Create a powerset of $ALL_FEATURES (the set of all subsets of $ALL_FEATURES).
 # We test all of the possible combinations (as long as we don't add too many
 # feature knobs this shouldn't take too long -- but the number of tested