The exception will be for an essential goal - such as work or caring responsibilities. Moving to Level 4 restrictions for a limited period in some areas, while not a decision we would ever take lightly because of the wider economic and social impact, would help us to address both of these concerns.
Under a level 4 lockdown pubs, restaurants and cafes have to close as well as non-essential shops will close, although businesses can offer takeaway menus.
1st LD: Scotland's toughest COVID-19 restrictions to be introduced in 11 council areas from Friday_china.org.cn
And she slapped a travel ban on all residents of those areas and others under level three restictions "except for certain essential purposes".
Areas entering into Level 4 on Friday include Glasgow, East Dunbartonshire, East Renfrewshire, Renfrewshire and West Dunbartonshire, North and South Lanarkshire, East and South Ayrshire, Stirling and West Lothian.
The City of Edinburgh, Clackmannanshire, Falkirk, Inverclyde, North Ayrshire, Dundee, Fife, Perth & Kinross and Angus all remain at Level 3; and Aberdeen City, Aberdeenshire, the Borders, Dumfries & Galloway, and Argyll & Bute at Level 2.More news: Tokyo reports record daily virus cases, outbreak locks down Australian state
The First Minister said there were "real reasons to be optimistic" about progress with the development of an effective vaccine.
She added: 'We will assess nearer the time the level that will apply in each area when the Level 4 restrictions end on December 11'.
"Pressure on hospitals in these areas - and on those who work in them - is already severe and with the additional pressure that the coming weeks may bring, it could easily become intolerable".More news: Ontario to get 2.4 million COVID-19 vaccines in early 2021: Elliott
"So it is essential that we all abide by travel restrictions".
"The clear advice of our public health experts is that we must drive infection rates down further in these areas".
The First Minister told MSPs: "I know people are frustrated that other restrictions have remained in place longer than planned".More news: Gordon Hayward reportedly declines player option, becomes free agent
"It is specifically meant to have an impact in advance of Christmas and the most challenging winter period".