What is the impact of using a poem in a leaflet?

It totally depends on the poem, the subject of the leaflet, and the person reading it. If the poem is well-written, fits the subject well, is short enough to be effective in a leaflet, and the reader is positive about the subject, then it could have a great impact. If any of those things break down, it might not work. Even the best poem in the world is going to fall flat on its face if it is about something the reader hates or doesn't believe in. It also might not be appropriate to the audience sometimes. For instance, if you are trying to recruit people to join your undergraduate degree program in computer programming, no matter *what* poem you use, no matter how compelling or perfect, is probably won't work. Most students interested in computer programming hate poetry.... not all (thankfully), but most. :) So, your recruitment drive might fail. On the other hand, if you get a short poem about God and how he cares about us... something that evokes feeling, and it is in a religious leaflet... it might work. You have to think about your audience and the purpose of your leaflet before you can decide whether it is appropriate.