More than 70 teachers in Scotland have been struck off in the past six years, according to figures obtained by BBC Scotland.
Nearly two-thirds of the 74 teachers removed from the teaching register since 2004-05 were struck off following criminal convictions.
Misconduct accounted for 26 of the cases, with two teachers being removed for incompetence.
The figures were released by the General Teaching Council for Scotland.
The council, which regulates the teaching profession in Scotland, revealed that 43 teachers were removed following criminal convictions after disciplinary hearings, while three others were struck off under the Protection of Children (Scotland) Act 2003.
At least 104 teachers have been removed from the GTCS register since 1998 but a breakdown of the reasons for their exclusion was only available from the 2004-05 academic year.
Figures have shown an upward trend in the past four years, with the number of removals climbing steadily from eight in 2006-07 to 18 in the last academic year.
The latest available figures do not include the case of a Fife teacher who was struck off this week for serious professional incompetence after a disciplinary hearing found she had caused "actual harm to the education of pupils in her care".
Other recent removals include another Fife teacher who had been caught using drugs in his car and a French teacher at Gordonstoun School who was found to have helped pupils cheat in exams.
The Education Institute of Scotland (EIS) teaching union said revised powers granted to the GTCS in 2006 over questions of competency were always likely to lead to a rise in the number of cases that were processed by the council.
An EIS spokesman said: "It is right that the GTCS should exercise its powers to continue to uphold the highest standards throughout the teaching profession in Scotland.
"All teachers want to see the very high standards set by Scottish education maintained, and the GTCS plays an important role in ensuring that this is the case."
The Scottish Secondary Teachers' Association pointed out that the figures represented a very small proportion of the 83,000 teachers registered in Scotland, but stressed the value it placed in the teaching council's role.
General secretary Ann Ballinger said: "I cannot overemphasise the importance of this work, ensuring that pupils are not taught by a teacher whose behaviour is unacceptable."
The Scottish Parent Teacher Council said parents wanted to know there was a robust system in place to ensure teachers who should not be in the classroom could be removed.
Executive director Eileen Prior said teaching was like any other profession with a small number who struggled to meet the demands of the job.
She added: "For them we look for a system which provides professional support and additional training to meet their needs but if the individual continues to fall short of the standard required then the system must also be in place to ensure that they are not teaching children.
"We would never expect large numbers of teachers to be struck off for incompetence, but we do need a system which can reach this point if needs be."