To create a strong logotype it is important to know what image you want your company/product/service/rock band to portray.
Often a simple typographic solution is the way forward.
Not all companies need a 'logo', this can often be a distraction if it's the wrong symbol.
If possible, create a brand new typeface so that your branding is unique, or, modify an existing font so that a new aspect becomes apparent.
Your identity needs to reflect the strengths and attributes of your business.
It should also convey some information on the core messages behind the brand.
This could be anything from 'a caring environment' to 'dynamic business solutions', depending on what you do.
A good designer will bring these messages to the identity using appropriate colour schemes, subtle use of type and clever iconography.
The best identities are the ones that stand the test of time, don't use the very latest fonts or illustration style if you don't want your identity to look dates within a couple of years, make sure you are not following fashion or copying your competitors.
It's usually a good idea to get your graphic designer to draw up a brand guidelines document for you once the identity has been agreed on.
This can be sent to other companies, partners or the press to ensure the identity does not get used in the wrong way.
The brand guidelines also ensures that the identity won't appear too small, on top of 'messy' images or in the wrong colours, all important to protect your precious brand!