One woman, whose stalker was sentenced to seven years in prison, has appealed to people in a similar situation to keep records.
Una Ring was speaking as a new Irish study found just 42% of respondents reported such incidents to An Garda Síochána.
The UCC report also revealed that, in most cases, the perpetrators were known to them.
Ms Ring, who co-founded Stalking Ireland, saw a co-worker plead guilty to a range of offences including harassment, criminal damage and attempted trespass with the intent to commit rape.
She told The Pat Kenny Show it still impacts her to this day.
"It had a profound impact on me," she said.
"I suppose it had positive [impacts] on the work that we did after, but very negative financially, mentally, emotionally.
"It's a very hard thing to go through because you're living on your nerves, essentially, 24 hours a day.
"You don't feel safe at home, you don't feel safe outside; even going from the front door to the car door.
"You're just nervous the whole time and it is very wearing and it is very debilitating.
"Once I went went public and I met Eve McDowell, the two of us decided that something needed to be done, and we set up Stalking Ireland".
'It doesn't leave you'
Ms Ring said her stalker is due for release next year.
"I'm still on medication," she said. "I'm still very anxious out and about, it really hasn't left me.
"He's due to be released next year so I'm already nervous about him getting out.
"It doesn't leave you, it really doesn't".
Ms Ring said she can understand why so many people may not go to Gardaí.
"I can understand it," she said.
"I suppose I was lucky in the way that my case progressed.
"I did go to them first - I printed off all the WhatsApp messages, text messages and the missed phone calls.
"Handy isn't the right word; but it was handy because he left all the evidence there.
"It was easy to prove that it was going on... he provided all the evidence himself, really".
Ms Ring said patterns are important to watch out for.
"If you see them one day, fine, but if you see them on separate occasions then there probably is an issue," she said.
"The most important thing to do, if you're weary of somebody on a certain day, [is to] mark down that day and continue reporting.
"If you do need to go to the Guards, you do need to have something to show that it's going on.
"You can't just go in and say, 'I think someone's following me' - you really do need to give them something".
She said this is "for their benefit and for your benefit as well."
"The onus is on the person who is being stalked; not to prove it, but to give the Guards something," she added.
Listen back to the full segment below:
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