My employer maintains and makes contributions to a Money Purchase Pension Plan and a Profit-Sharing Plan. I do not make any contributions to the plan nor take any deductions. I was wondering if I can open and make contributions to a Roth IRA? Or does my participation in my employer's plan prevent this? What issues do I need to investigate?

Your employer's plan is not a factor. The biggest hurdle is modified adjusted gross income, a single person must have $95,000 or less and married person's filing a joint return $150,000 or less of modified adjusted gross income in order to contribute the full $2,000.

A reduced deduction is allowed if a single person has modified adjusted gross income of $110,000 or less but more than $95,000; a similar phase-out range between $150,000 and $160,000 applies for marrieds filing jointly.

You must also have $2,000 of earned income but I assumed that was a given because you're covered by an employer plan.