A pilot study by the Association of Catholics in Ireland (ACI) has found there is "serious concern" about active lay involvement in parishes.
It is calling on Irish bishops to commission a countrywide survey to identify the key issues, prior to holding a national synod about the way forward for the church.
The study looked at the role of pastoral councils, the prevalence of adult faith formation, the extent of family catechesis, and the source of and the reading of the prayers of the faithful at mass.
It was conducted on an all-island basis across 36 parishes.
It found that 67% had parish pastoral councils, but 54% regarded them as ineffective.
While just 41% had adult faith development activities, 50% reported no encouragement for family catechesis.
And only 52% had lay-led prayer services in the absence of a priest.
The study also found that lay parishioners prepared the prayers of the faithful for mass in only 17% of parishes - but were read by laity in 54% of parishes.
ACI wants the Irish Catholic Bishops' Conference to commission a countrywide survey with a view to identifying the key issues which have to be addressed to ensure "the survival of the Christian ethos" in parishes across the country.
It says this should be in the context of the diminishing numbers of priests and an ageing cohort of lay faithful attending church.
A full diocesan synod should be carried out in every diocese across the country, they add.
"The natural 'next step' would be to call a national synod with the full involvement of the baptised lay faithful to discern a way forward which will seek to guide the church in Ireland in the years ahead", a statement says.