Increasing response rates?

I try to hide from all of my alumni responsibilities. It seems like eons ago that I graduated and I don't keep in touch with anyone that was in my class or in my program. I recently moved and thought that might be the end of the newsletter that I would get and pitch into the recycling before I even got it in my house, but they are very crafty and have found me once again. I basically treat all of my alumni info like I do my copy of 'Cigar Aficionado" magazine, which I have never ordered. I smoked one cigar in my life and thought it was extremely nasty.
That said, you need to find a way to break through the clutter and raise interest. What type of subject line would draw people in? Can you offer other prizes that may not be monetary but still valuable (20 minute zoom call with a professor, free library pass for a quarter)?
You might also offer to share results with alumni that filled out the survey. This might be especially interesting if your survey includes current salary or other benchmarks that people would be interested in comparing themselves to others.
In your job, if you routinely talk to alumni, I would add in some questions about what would motivate them to take a survey, they might have some relevant ideas that you could incorporate into your survey invitation.

For our graduate survey, this time I asked each academic department chair to provide text for a personalized email invite for graduates from their majors. About 1/2 of the chairs provided something, and for those my response rate was at least 1/3rd higher than for those graduates who got a generic email.
Yes it added some work on the front end to set up the separate distributions for those with personalized emails for their majors, but it made a big difference.

Thanks for the responses! They are very good suggestions which I will try to implement in future surveys. Having the deans send out initial emails to their graduates this year seemed to have helped slightly (I am still collecting responses, but at this point the response is slightly higher).
Daniel, I do appreciate your insights. You have given me some good things to think about. I did change the subject line from last year and will think about how I can make it more attractive. We do post a summary of results on our webpage. But, after reading your input, it might be worth it for us to send and more detailed report to those who responded to the survey. I do not have contact with students in my job, but perhaps I could suggest that the professors ask their students what we could do to motivate them to fill out the survey.

Thank you for the discussion. I am using a survey for my MSc at UoG. In establishing if a reward was needed to complete the survey where the respondents would be sharing their perspectives to contribute to the creation of the Becoming of an Ontario Shared Rural Vision, I agonized over the type of motivation needed to partake into such an endeavour. I came to recognize that in any place-based development the trigger or the glue must be intrinsic motivation.
I decided to set sail with that simple basic assumption. The challenge was for me to have questions that I, as a respondent, would want to answer to contribute to a vision for my rural community socio-economic, cultural vitality and evolution. I designed 19 questions for the survey. The survey is on-going and will be closed in five more days. The response has been reasonable so far. I may not know the real motivation of the participants and what motivated them to participate.
As the research project has a feedback loop through one more survey, I will find a way with my advisor to seek some input though this was not the goal of the research nor what REB approved it for.
A very interesting point to consider as it is because of participation that surveys inform!