The FTSE 250-listed investment group said it is anticipated that Boylan will join its board, subject to regulatory approvals, in early 2019.
READ: Brewin Dolphin announces surprise departure of finance director Andrew Westenberger from May 16
Back at the end of April, Brewin Dolphin announced the surprise departure of its finance director Andrew Westenberger, who left by mutual agreement on May 16.
The company said then that it had already started a search for a permanent replacement for Westenberger, who had been finance director at the group for five years.
In a regulatory announcement on Monday, the firm noted that Boylan has been the finance boss for LGIM, one of Europe's leading asset managers, for the last five years.
Prior to that, it added, she worked at Aviva PLC (LON:AV.) for 12 years where she held several senior roles, including CFO of Aviva North America, and CFO of Aviva Investors from 2007 to 2011.
David Nicol, Brewin Dolphin’s chief executive said: "We are delighted that we have hired someone of Siobhan's outstanding calibre. She has a tremendous track record at several high-profile institutions.
“She will bring her in-depth knowledge of the financial services industry, as well as management and technical skills, to Brewin Dolphin at a critical stage in our growth trajectory."