Match unique values between two colums

Hello,

I am completely ignorant about VBA, but I learn by doing, so I hope someone can help me with this.

I need to list distinct values corresponding to a distinct value in another column. I was able to do it with an array formula : =INDEX(namedarray,MATCH(0,COUNTIF($B$1:B1,namedarray),0)) , but the several array formulas in the page really, really slow down processing.

So, the there are two columns, say A and B, and I need to list all the instances where A and B are together as a unique combination.

Please let me know if I've done a completely **** job at explaining what I need. Thank you.

Thank you for your answers. Now that I am at work, I will see if I can resolve my problem with the suggestions given. Thanks.