Looking for resources (or personal tips/suggestions) on developing higher client conversion rates

[Toddfoster]

I work for a local Canadian digital marketing company and we are seeking to expand our client base but are having difficulty with converting potential clients. We do excellent work and get good results across the board for our current customers. That being said, we can't seem to convert new ones at the rate we hope to. I am wondering what we are missing and would really like to see what has worked for others to see if we can augment our approach to be more successful. Any ideas are greatly appreciated!

We are currently beating the competition on local SERPs, and rank very well nationally. 
We have run AdWords campaigns, attempted cold-calling, worked with website audits, worked with different sales funnel ideas, social media and done our share of outreach in both online and local communities, among other marketing moves. Tips on these topics are also welcome, because it is possible we just went about it the wrong way.

[Ray-pp]

Hi Rob,

One strategy I didn't see mentioned was the use of Case Studies. Case studies can be used to help convert clients with similar goals - they add a lot of confidence in the ability of the service provider and provide a direct example of success.

I also suggest getting on the phone as often as possible with potential clients. I've found it much easier to convert a client when speaking to the client's needs directly over the phone. Sometimes, the goals and needs can get lost in email and speaking with them directly allows me to align both parties; and a sense of unity is a great conversion tactic.