Re: Website Link
I think you are saying that you have your own website, and one if its pages is a "portfolio" containing links pointing to work you have previously done.
Each link would contain a web address of somebody's website, namely a website which you set up for a client.
When you refer to "linking" you mean that the web address on your site would be "live" and that if someone visiting your site points to and clicks on that link, his browser would then access the website of that address.
I do not know of any legal principle that would generally prevent a web designer from doing this, in the absence of an agreement to the contrary. Of course it would not be proper to imply that one has designed a website if she hasn't actually done that work, and it would be appropriate to check periodically to confirm that the website is still representative of one's handiwork.
Also, there are certain professions, such as being a lawyer, where one is obliged to keep the identity of one's clients confidential unless they expressly permit it. If one is in such a profession, or if one has agreed with the client to maintain confidentiality, then one is obliged to refrain from placing such a link without permission on one's website.
