Kevin -
I would not want to invite multiple vendors to the same meeting. I would think there may be confidentiality issues (particularly if they are competitors). I believe the business owner (relationship owner) should hold quarterly meetings with their vendors, and review SLAs and roadmap.
I also don't think you can expect all your vendors to do this. I think only vendors with whom you have a certain threshold of dollar business would want to engage with you this way. Speaking as a vendor, they are likely not staffed to meet quarterly with each of their customers.
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Kate Wakefield, CISSP / CIPT / CRISC
Infoblox Director of GRC
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