The former Yeovil chief’s appointment for the rest of the season will be confirmed by the club today.
Slade, 48, is the man the Seagulls are pinning their faith in to steer the Seagulls clear of relegation trouble in League One.
If he achieves that target then he will be in a very strong position to land the post on a more permanent basis.
The experienced Slade left Yeovil last month after four straight wins, because of differences with the Board over finances and the club’s lack of ambition.
He arrives at Withdean with an excellent record of success with unfashionable clubs in the lower divisions.
Scarborough looked doomed to relegation from the Conference when he kept them up seven years ago.
He guided Grimsby to the League Two play-off final in 2005-2006 and Yeovil to the League One final the following season after knocking out Nottingham Forest.
The appointment of Slade ends a saga which began with the departure of Micky Adams by mutual consent a fortnight ago.
Stockport chief Jim Gannon rejected the job last week and former Blackburn boss Paul Ince turned down talks earlier this week.
Slade faces a quick reunion with Yeovil.
They are at Withdean on Saturday week after tomorrow’s trip to relegation rivals Leyton Orient and his first home game in charge against Southend next Tuesday.