Addressing around 300 people in a speech in the Creggan area of Derry, the Northern Ireland Deputy First Minister said there could be "no return to the violence and repression that scarred this society for so long".
On August 31,1994, the IRA announced a complete cessation of military operations. Just weeks later loyalist paramilitaries also announced a ceasefire.
Mr McGuinness has previously described the IRA ceasefire as the most important peace-making decision in the past 100 years of Irish history.
Yesterday he said there was an enormous onus "on those who recognise the enormous progress we have made, and continue to make, since the IRA cessation in 1994 to make their voices heard".
"In 1994, dialogue offered the only way out of perpetual conflict and Irish republicans entered that dialogue confidently," he said.
"There can be no return to the violence and repression that scarred this society for so long. Successive agreements supported by the vast majority of the Irish people have removed any rationale for armed struggle and have put in place peaceful and democratic alternatives."