One observation that he makes is that, as we become involved in church and growing in our faith, we surround ourselves with fellow believers. While this is great for our growth, it unfortunately isolates us from the lost world we are commissioned to reach. I have found that to be true of my own life. I have taken the challenge seriously and am asking the Lord for a greater awareness of my opportunities. This study gives some wonderful ideas about how to share your testimony, as well as ways to engage the world around you in a natural and inviting way. I think you will enjoy Bill Hybels' conversational style of teaching.
You can find this study under the subject heading of "Evangelism".