I call all the time... I follow-up all the time.

"Yet again?" Yes, again I am snatching insights from my Linkedin Q&A responses because my creative powers are as great as those of a rock. Enjoy and weigh in at your convenience.

When you cold call, how often do you follow up?
Particularly with warm leads, how often do you call back? Is there a rule of thumb? Does it change depending on the industry and the size of the prospect. In addition to follow-up phone calls, what other types of follow-up do you use - snail mail, email, newsletters etc. Do you use multiple methods? What works best for you?

Thanks for posting such insightful questions. I have a process developed for managing prospect interactions throughtout the lead generation, cold calling and inside sales effort:
Identify
Qualify
Develop
Close
Follow-up

It acts more as a continuum than a linear cycle because you may not always run through the steps in a specific order.

In my opinion, one of the most important aspects of the continuum is Follow-up because this maintains the essential connection between the sales person and their prospect. I follow-up at every scheduled junction of an interaction once the opportunity is classified as "warm" because it maintains continuity. I might add, not to an excessive or overbearing extent but to insure that "up front contracts" (Sandler Selling System) or incremental actions are achieved to keep the process moving along smoothly.

The follow-up can take the form of email, snail mail, LinkedIn note, phone call, text message, IM and whatever comes to mind as a courteous and non obtrusive method. Most importantly, the prospect must understand your intention and expectation for the follow-up and be agreeable to the interaction. I believe that my time is equally valuable when entering into an interaction with a prospect and I will return fire (agreeably) when necessary to insure our interests align to establish mutual sincerity and expectation.

Lastly, I am a proponent of calling so my knee jerk follow-up response is typically by phone unless otherwise designated by the prospect. Ultimately, follow-up efforts will be immensely successful as long as you maintain open communication with your prospect, setting expectations... and sticking to them.