A method is provided for separating or dividing strengthened glass articles, particularly strengthened glass sheets, into at least two pieces, one of which has a predetermined shape and/or dimension. A flaw is initiated in the glass at a depth that is greater than the depth of the strengthened surface layer of the glass, and a vent extending from the flaw is created at a vent depth that is greater than the depth of and outside the strengthened surface layer to at least partially separate the glass. In one embodiment, the vent is generated by treating the glass with a laser to heat the glass to a temperature in a range from about 50° C. below the strain point of the glass up to a temperature between the strain point and the anneal point of the glass. A glass article having at least one strengthened surface and at least one edge having an average edge strength of at least 200 MPa is also described.