diff --git a/hack/test-cmd.sh b/hack/test-cmd.sh
index 7704db2904f..2221df6892f 100755
--- a/hack/test-cmd.sh
+++ b/hack/test-cmd.sh
@@ -147,6 +147,16 @@ IMAGE_PERL="gcr.io/google-containers/perl"
 # ensure ~/.kube/config isn't loaded by tests
 HOME="${KUBE_TEMP}"
 
+# Find a standard sed instance for use with edit scripts
+SED=sed
+if which gsed &>/dev/null; then
+  SED=gsed
+fi
+if ! ($SED --version 2>&1 | grep -q GNU); then
+  echo "!!! GNU sed is required.  If on OS X, use 'brew install gnu-sed'."
+  exit 1
+fi
+
 # Check kubectl
 kube::log::status "Running kubectl with no options"
 "${KUBE_OUTPUT_HOSTBIN}/kubectl"
@@ -314,7 +324,7 @@ runTests() {
   kubectl config set clusters.test-cluster.certificate-authority-data "$cert_data" --set-raw-bytes
   r_writen=$(kubectl config view --raw -o jsonpath='{.clusters[?(@.name == "test-cluster")].cluster.certificate-authority-data}')
 
-  encoded=$(echo -n "$cert_data" | base64 --wrap=0)
+  encoded=$(echo -n "$cert_data" | base64)
   kubectl config set clusters.test-cluster.certificate-authority-data "$encoded"
   e_writen=$(kubectl config view --raw -o jsonpath='{.clusters[?(@.name == "test-cluster")].cluster.certificate-authority-data}')
 
@@ -439,7 +449,7 @@ runTests() {
   create_and_use_new_namespace
   kube::test::get_object_assert pods "{{range.items}}{{$id_field}}:{{end}}" ''
   # Command
-  echo "${output_pod}" | sed '/namespace:/d' | kubectl create -f - "${kube_flags[@]}"
+  echo "${output_pod}" | $SED '/namespace:/d' | kubectl create -f - "${kube_flags[@]}"
   # Post-condition: valid-pod POD is created
   kube::test::get_object_assert pods "{{range.items}}{{$id_field}}:{{end}}" 'valid-pod:'
 
@@ -678,7 +688,7 @@ runTests() {
 
   ## --force replace pod can change other field, e.g., spec.container.name
   # Command
-  kubectl get "${kube_flags[@]}" pod valid-pod -o json | sed 's/"kubernetes-serve-hostname"/"replaced-k8s-serve-hostname"/g' > /tmp/tmp-valid-pod.json
+  kubectl get "${kube_flags[@]}" pod valid-pod -o json | $SED 's/"kubernetes-serve-hostname"/"replaced-k8s-serve-hostname"/g' > /tmp/tmp-valid-pod.json
   kubectl replace "${kube_flags[@]}" --force -f /tmp/tmp-valid-pod.json
   # Post-condition: spec.container.name = "replaced-k8s-serve-hostname"
   kube::test::get_object_assert 'pod valid-pod' "{{(index .spec.containers 0).name}}" 'replaced-k8s-serve-hostname'
@@ -711,7 +721,7 @@ __EOF__
   kubectl delete node node-${version}-test "${kube_flags[@]}"
 
   ## kubectl edit can update the image field of a POD. tmp-editor.sh is a fake editor
-  echo -e '#!/bin/bash\nsed -i "s/nginx/gcr.io\/google_containers\/serve_hostname/g" $1' > /tmp/tmp-editor.sh
+  echo -e "#!/bin/bash\n$SED -i \"s/nginx/gcr.io\/google_containers\/serve_hostname/g\" \$1" > /tmp/tmp-editor.sh
   chmod +x /tmp/tmp-editor.sh
   # Pre-condition: valid-pod POD has image nginx
   kube::test::get_object_assert pods "{{range.items}}{{$image_field}}:{{end}}" 'nginx:'
@@ -780,7 +790,7 @@ __EOF__
   # Post-Condition: pod "test-pod" doesn't have configuration annotation
   ! [[ "$(kubectl get pods test-pod -o yaml "${kube_flags[@]}" | grep kubectl.kubernetes.io/last-applied-configuration)" ]]
   ## 2. kubectl replace doesn't set the annotation
-  kubectl get pods test-pod -o yaml "${kube_flags[@]}" | sed 's/test-pod-label/test-pod-replaced/g' > "${KUBE_TEMP}"/test-pod-replace.yaml
+  kubectl get pods test-pod -o yaml "${kube_flags[@]}" | $SED 's/test-pod-label/test-pod-replaced/g' > "${KUBE_TEMP}"/test-pod-replace.yaml
   # Command: replace the pod "test-pod"
   kubectl replace -f "${KUBE_TEMP}"/test-pod-replace.yaml "${kube_flags[@]}"
   # Post-Condition: pod "test-pod" is replaced
@@ -796,7 +806,7 @@ __EOF__
   [[ "$(kubectl get pods test-pod -o yaml "${kube_flags[@]}" | grep kubectl.kubernetes.io/last-applied-configuration)" ]]
   kubectl get pods test-pod -o yaml "${kube_flags[@]}" | grep kubectl.kubernetes.io/last-applied-configuration > "${KUBE_TEMP}"/annotation-configuration
   ## 4. kubectl replace updates an existing annotation
-  kubectl get pods test-pod -o yaml "${kube_flags[@]}" | sed 's/test-pod-applied/test-pod-replaced/g' > "${KUBE_TEMP}"/test-pod-replace.yaml
+  kubectl get pods test-pod -o yaml "${kube_flags[@]}" | $SED 's/test-pod-applied/test-pod-replaced/g' > "${KUBE_TEMP}"/test-pod-replace.yaml
   # Command: replace the pod "test-pod"
   kubectl replace -f "${KUBE_TEMP}"/test-pod-replace.yaml "${kube_flags[@]}"
   # Post-Condition: pod "test-pod" is replaced
@@ -828,7 +838,7 @@ __EOF__
   ! [[ "$(kubectl get pods test-pod -o yaml "${kube_flags[@]}" | grep kubectl.kubernetes.io/last-applied-configuration)" ]]
   # Command: edit the pod "test-pod"
   temp_editor="${KUBE_TEMP}/tmp-editor.sh"
-  echo -e '#!/bin/bash\nsed -i "s/test-pod-label/test-pod-label-edited/g" $@' > "${temp_editor}"
+  echo -e "#!/bin/bash\n$SED -i \"s/test-pod-label/test-pod-label-edited/g\" \$@" > "${temp_editor}"
   chmod +x "${temp_editor}"
   EDITOR=${temp_editor} kubectl edit pod test-pod --save-config "${kube_flags[@]}"
   # Post-Condition: pod "test-pod" has configuration annotation
@@ -1951,7 +1961,7 @@ __EOF__
     fi
     # Command: kubectl edit multiple resources
     temp_editor="${KUBE_TEMP}/tmp-editor.sh"
-    echo -e '#!/bin/bash\nsed -i "s/status\:\ replaced/status\:\ edited/g" $@' > "${temp_editor}"
+    echo -e "#!/bin/bash\n$SED -i \"s/status\:\ replaced/status\:\ edited/g\" \$@" > "${temp_editor}"
     chmod +x "${temp_editor}"
     EDITOR="${temp_editor}" kubectl edit "${kube_flags[@]}" -f "${file}"
     # Post-condition: mock service (and mock2) and mock rc (and mock2) are edited