In an unconventional move, Mr Kenny gave over three of the 11 nominations to Mr Martin.
Two former ministers and a number of failed Fine Gael TDs have also been chosen among Mr Kenny’s nominees to the Seanad.
But opposition party Fianna Fáil were given the power to select three people — Joan Freeman, founder of Pieta House; Aer Arann founder Pádraig Ó Céidigh, and Colette Kelleher, CEO of Alzheimers Ireland.
Speaking after her nomination Ms Freeman said: “I found out yesterday afternoon, I got a wonderful call from Micheál Martin asking whether I would consider it. He said would I consider being the voice for mental health and I think they were the most important words I could have heard.
“Three of the nominations were given to Micheál Martin and he had the right and the ability to chose a person that he might work well for this country,” she told RTE’s Drivetime programme.
“We campaigned for reform of the Seanad and as part of that government reform we asked that we would have the option of naming three members to the Seanad,” a Fianna Fáil spokesman said.
Former Children’s Minister James Reilly has also been selected by Mr Kenny to join the Upper House meaning he may now stay on as deputy leader of Fine Gael.
Six of the 11 chosen by the Taoiseach are former Fine Gael TDs and this also includes former junior environment minister Paudie Coffey, who lost his seat in the recent general election.
Other TDs who failed to retain their seats who have been selected are Michelle Mulherrin, Ray Butler, Frank Feighan, and John O’Mahony.
Mr Kenny has also selected Billy Lawless who is an advocate for Irish immigrants in the US as one of his nominees.
Broadcaster Marie-Louise O’Donnell, who was among Mr Kenny’s nominees in 2011, has been selected again.
However, a number of people who had been tipped for positions missed out, including former ministers Jimmy Deenihan and Tom Hayes, and Anne-Marie Dermody and Averil Power.
Meanwhile no location has yet been found to house the Seanad while extensive restoration and refurbishment work is carried out on Leinster House.
The National Museum and City Hall have both been suggested , while another option is the possibility of holding the Seanad in the Dáil chamber on non-sitting days.