diff --git a/CHANGELOG-Nns-Dapp-unreleased.md b/CHANGELOG-Nns-Dapp-unreleased.md
index 65697678b23..98ab1031b62 100644
--- a/CHANGELOG-Nns-Dapp-unreleased.md
+++ b/CHANGELOG-Nns-Dapp-unreleased.md
@@ -58,6 +58,7 @@ proposal is successful, the changes it released will be moved from this file to
 * Update `dfx` to `v0.15.1`.
 * Update the URL of the app subnet to what dfx v15 expects.
 * Use a unique branch when updating the snsdemo release, didc, IC candid files or rust.
+* Better checks that the network is defined.
 
 #### Deprecated
 
diff --git a/scripts/network-config b/scripts/network-config
index 4d87d7c9d0d..f5e1be77a2c 100755
--- a/scripts/network-config
+++ b/scripts/network-config
@@ -15,6 +15,14 @@ assert_dfx_network_var_is_set() {
     echo "ERROR: DFX_NETWORK is not defined."
     return 1
   } >&2
+  # Note: ${var@a} gets variable attributes.  It has been available in bash since bash 5.1, so is as old as Node14.
+  #       'x' is the export attribute.
+  #       If we find that we need to support older systems, please use this instead:
+  #         bash -c 'test -n "${DFX_NETWORK:-}"' || { ...
+  [[ "${DFX_NETWORK@a}" == *x* ]] || {
+    echo "ERROR: DFX_NETWORK is not exported."
+    return 1
+  }
 }
 # Gets the global network configuration.  If missing, the answer is null and the return-value 1.
 global_network_config() {
@@ -33,6 +41,7 @@ local_network_config() {
 }
 # Checks that the DFX_NETWORK is configured
 assert_dfx_network_var_is_configured() {
+  assert_dfx_network_var_is_set || return
   local_network_config >/dev/null || global_network_config >/dev/null || {
     echo "ERROR: DFX_NETWORK '$DFX_NETWORK' is not defined in dfx.json or $GLOBAL_NETWORK_CONFIG_FILE"
     echo "Available networks are:"
diff --git a/scripts/network-config.test b/scripts/network-config.test
index 47bf58a6eaa..dd4d70c5b44 100755
--- a/scripts/network-config.test
+++ b/scripts/network-config.test
@@ -170,19 +170,41 @@ title() {
     } >&2
   fi
 )
-(
-  title "assert_dfx_network_var_is_set should fail when the network is unset"
-  mk_env
-  unset DFX_NETWORK
-  if assert_dfx_network_var_is_set 2>/dev/null; then
-    {
-      echo "FAIL"
+for command in assert_dfx_network_var_is_set assert_dfx_network_var_is_configured global_network_config local_network_config network_config; do
+  (
+    title "$command should fail when the network is unset"
+    mk_env
+    unset DFX_NETWORK
+    if "$command" 2>/dev/null; then
+      {
+        echo "FAIL"
+        exit 1
+      } >&2
+    else
+      echo OK
+    fi
+  )
+  (
+    title "$command should fail when the network is defined but not exported"
+    mk_env
+    DFX_NETWORK=gobbeldygook
+    if actual_stderr="$("$command" 2>&1)"; then
+      {
+        echo "FAIL: $command should have returned non-zero."
+        exit 1
+      } >&2
+    else
+      echo OK
+    fi
+    expected_stderr="ERROR: DFX_NETWORK is not exported."
+    [[ "${expected_stderr}" == "${actual_stderr}" ]] || {
+      echo "FAIL: The error emitted by $command should state explicitly that DFX_NETWORK should be exported."
+      echo "Expected: $expected_stderr"
+      echo "Actual:   $actual_stderr"
       exit 1
     } >&2
-  else
-    echo OK
-  fi
-)
+  )
+done
 (
   title "global_network_config should be able to get a globally defined network"
   mk_env