Change Opportunity status in Accounts workflow

Change Opportunity status in Accounts workflow

Hi,

I'm trying to set up a workflow where I can change the Opportunity status (an opportunity created for an account), but I can't figure it out.

I've made a workflow to change fields and add tasks when an account is changed from "Prospect" to "Client"
I want to change the connected opportunity to a different status within the same (or a new?) workflow. So when the account is changed from prospect to client, it should trigger the opportunity status to be changed as well.

Any ideas?

Edith de Neef.