Georgina Gharsallah from Worthing will be featured on the Crimewatch Roadshow in March to coincide with the year anniversary of her disappearance.
Mother-of-two Georgina, 31, was last seen leaving the Clifton Food and Wine off licence store in Clifton Road, Worthing, at 9.30am on Wednesday, March 7.
The episode, which will air on March 12 across the country, will feature CCTV footage of her last sighting and an appeal for information.
Her mother Andrea Gharsallah will be travelling to Cardiff, where Crimewatch Roadshow is filmed, to appear on the show.
She hoped the high-profile appearance would rekindle sightings that have otherwise dried up.
She said: "I want to say I'm hopeful, but it has been a year and we have had nothing.
"It's one more thing to keep Georgina's story out there. It is nationwide, which is the most important thing."
It came about after Sussex Police suggested featuring Georgina's case to producers.
Missing person adverts will also be appearing in bus shelters in Worthing, Portsmouth, Brighton and other large towns, and Andrea and her relatives will be staging their own reconstruction of what may have happened.
To mark one year since Georgina's disappearance, a candle-lit vigil will be held at Worthing railway station on March 7 from 7pm until 8pm and they will be releasing balloons.