diff --git a/README.md b/README.md
index 269481016e9..2e8dbfb0542 100755
--- a/README.md
+++ b/README.md
@@ -96,6 +96,36 @@ The `load_fake_data` command will output pages with the following slugs:
 
 This list is available on review apps by clicking on `DEV HELP` in the menu or going to `[review app url]/help`.
 
+### Using a copy of the production database for critical testing
+
+Some development work requires testing changes against "whatever the current production database looks like", which requires having postgresql installed locally (`brew install postgresql` on mac; download and run the official installer for windowsl; if you use linux/unix, you know how to install things for your favourite flavour, so just do that for postgresql).
+
+The steps involved in cloning the production database for local use are as follows:
+
+1) grab a copy of the production database by running `pg_dump DATABASE_URL > foundation.psql` on the commandline. In this, `DATABASE_URL` is a placeholder, and you will want to replace it with the value found for the `DATABASE_URL` environment variable that is used on heroku, for the production instance.
+
+This will take a little while, but once the operation  finishes, open `foundation.psql` in your favourite text/code editor and take note of who the owner is by looking for the following statements:
+
+```
+SET search_path = public, pg_catalog;
+
+--
+-- Name: clean_user_data(); Type: FUNCTION; Schema: public; Owner: ...... <= we want to know this string
+--
+```
+
+2) Run `createdb foundation` on the command line so that you have a postgresql database to work with. If you get an error that you already have a database called `foundation`, either create a new database with a new name (and then use that name in the next steps) or delete the old database using `dropdb foundation` before issuing `createdb foundation`.
+
+3) Run `psql foundation` on the command line to connect to that database.
+
+4) Run `CREATE ROLE TheOwnerNameFromTheDBdump WITH SUPERUSER;` in the postgresql command line interface, making sure to have that semi-colon at the end, and making sure NOT to quote the owner name string.
+
+5) Run `\i foundation.psql` in the postgresql command line interface to import the `foundation` database content. Once this finishes you will have an exact copy of the production database set up for local testing.
+
+You will now also need to update your `.env` file to make sure you're using this database, setting `DATABASE_URL=postgres://localhost:5432/foundation`.
+
+If you need to reset this database, rerun step 2 (with `dropdb foundation` as first command) through 5 to get back to a clean copy of the production database.
+
 ### Running the project for front-end development
 
 - At the root of the project you can run: `npm start`, which will start the server as well as watch tasks for recompiling changes to JS(X) and Sass files.