What is the state of the law on an undertaking of confidentiality?

In Schreiber v. Canada (Attorney General) 2000 ABQB 536, Burrows J. characterised the policy reasons underlying the undertaking of confidentiality in the following way, at para. 12: The requirement that a litigant submit to discovery is an intrusion on the litigant’s interest in privacy and confidentiality of private information. That intrusion is permitted in order to ensure that there is full disclosure, and therefore a better chance of a just result, in the action in which the discovery occurs. The implied undertaking exists to limit the effect of the intrusion by ensuring that the information is used only for the purpose for which the litigant is obliged to provide it.