Margaret Caldwell met Dorothy Bain QC on Monday in Glasgow to discuss the unsolved murder case, telling reporters afterwards that she was “very happy about how things went”.
Ms Bain was said to have accepted that mistakes were made in investigations into Emma Caldwell’s death.
Ms Caldwell, 27, had been working as a prostitute when her body was found in woods near Biggar, South Lanarkshire, in May 2005.
The unsolved case was reopened in 2015 following consideration by senior lawyers in the Crown Office and tireless campaigning by her mother.
Mrs Caldwell’s solicitor, Aamer Anwar, told reporters outside the Procurator Fiscal’s office in Glasgow: “A very detailed discussion took place of the Crown Office’s strategy but nothing can be said which prejudices the ongoing inquiry and its integrity.”
Mr Anwar said in a statement on behalf of Mrs Caldwell: “When Emma was brutally murdered 16 years ago her family, in the midst of their grief, were forced to campaign for justice.
“Emma’s father, William, before he died in 2011, made his family promise they would never give up fighting for justice.
“Since then, Margaret has been made many promises by former lord advocates but as the years passed hope faded.
“There should never be a time limit on justice and Margaret feels she was betrayed by the original Strathclyde Police investigation but has confidence that the new Police Scotland investigation has left no stone unturned.
“Margaret welcomed today’s meeting with the new Lord Advocate, Dorothy Bain QC – she was the first Lord Advocate to say that it is not right that the investigation has taken so long and accepted that mistakes have been made.
“The Lord Advocate has renewed once again Margaret’s hope for justice.”
Ms Bain, sworn in as Scotland’s most senior law officer last month, replacing James Wolffe QC, counts securing the first murder conviction against serial killer Peter Tobin among her legal achievements.
Taking up her role, she said: “The trust placed in public prosecutors is the most significant that a society can bestow. I do not carry that responsibility lightly and promise to pursue this vital public service to the utmost of my abilities.
“The serious cases I have been involved in have given me an unshakeable belief in the importance of the public service prosecutors perform in delivering justice for communities, in giving victims a voice in court and in protecting the rights of people accused of crime.”