Interviews Quadrupled. The Reason Sairyu Reintroduced Recruitment Support They Once Canceled? Case Study Released

CASTER Inc. (Headquarters: Chiyoda-ku, Tokyo; Representative Director: Shota Nakagawa; hereinafter "CASTER") announced a case study where Sairyu Inc. (Headquarters: Chuo-ku, Tokyo; Representative Director & President: Kota Kurihara; hereinafter "Sairyu"), a consulting company specializing in new business development and sales/marketing support, reintroduced its recruitment support service "CASTER BIZ recruiting," achieving stable candidate pool formation and efficient recruitment operations.

Approximately five years ago, Sairyu introduced CASTER BIZ recruiting during the early stages of establishing its recruitment infrastructure. Once the required number of hires was met, they terminated the contract. Since then, they have expanded their organization primarily through referral hiring. However, with business growth, the need to ensure a stable "volume" and "speed" in recruitment activities has increased. This case study delves into the background of how the reintroduction led to approximately a fourfold increase in interviews and the establishment of a "scalable recruitment system" not dependent on fixed costs.

■ Background of Introduction: The Limits of Referral Hiring and the Evolution of "Recruitment Worries" with Phases

Sairyu first introduced "CASTER BIZ recruiting" about five years ago. At that time, it was used to establish a recruitment foundation, and upon achieving their hiring goals, they switched to in-house management (centered on referral hiring). However, with further business expansion, they faced the following new challenges:

Limits of Referral Hiring: Relying solely on employee referrals led to fluctuations in candidate pool formation, making planned recruitment difficult.

Difficulty in Securing Activity Volume: Without dedicated recruitment staff, non-core tasks from scouting to scheduling put an increased burden on management and on-site teams.

Lack of Reproducibility: A system was needed to maintain stable contact with candidates without depending on the workload of individual staff members.

To address these "phase changes," they decided to reintroduce CASTER BIZ recruiting, not as mere operational support, but as a "partner" capable of flexibly controlling the volume and speed of recruitment.

■ Support Provided by "CASTER BIZ recruiting"

• Creation of scout messages and sending scouts

• Responding to candidate replies and initial contact

• Scheduling casual interviews and formal interviews

• Follow-up with candidates who decline offers

• Sharing and organizing casual interview recordings

• Organizing text-based selection information and candidate evaluations

• Support for organizing and improving the overall recruitment operation

■ Introduction Results

• Eliminated the personalization of recruitment activities, standardizing operations from candidate pool formation to the initial selection stages.

• Improved the reproducibility of recruitment activities through stable scout sending volume and candidate response.

• Casual interviews increased from 5-6 per month to over 20 per month, approximately a fourfold increase.

• Reduced the workload of recruitment staff, enabling them to focus on core tasks such as decision-making and strategy design.

• Achieved a "scalable recruitment system" that is not dependent on fixed costs and can be adjusted according to business growth.

■ Future Developments

CASTER will support growing companies in building flexible recruitment systems to address challenges such as recruitment resource shortages and the personalization of recruitment tasks.

Through CASTER BIZ recruiting, by stably supporting operations from candidate pool formation to initial selection, we will boost the realization of "scalable recruitment operations" that allow companies to adjust activity volume according to their recruitment phase and business growth.

As a BPaaS partner that establishes recruitment not as a temporary measure but as a continuously running mechanism, we will walk alongside companies in their sustained growth.

■ Article summarizing the background and results of the introduction:

URL ： https://recruiting.cast-er.com/case/sairu/

■About CASTER BIZ recruiting

"CASTER BIZ recruiting" is a specialized recruitment service that handles the entire range of recruitment tasks, from strategy planning to operational execution. Based on cumulative support for over 800 accounts, it promotes recruitment activities logically and efficiently. It liberates HR personnel from recruitment tasks, providing an experience where "interviews with desired candidates are scheduled just by keeping your calendar open."

CASTER BIZ recruiting service site：https://recruiting.cast-er.com/

■ About CASTER

Under the mission "Recreate Everything about Work," CASTER supports companies' productivity improvement and sustainable growth through AI x BPaaS. Since its founding in 2014, the company has operated entirely remotely and has supported over 6,000 cumulative accounts through businesses such as the "CASTER BIZ" series of online assistants (No. 1 in adoption companies (*1)). In the AI era, we lead new ways of working and recreate the "world of work" through the collaboration of AI and humans.

＜Company Overview＞

Company Name　　　　：CASTER Inc.

Listed Market　　　：Tokyo Stock Exchange Growth Market, Securities Code 9331

Representative　　　　：Shota Nakagawa, Representative Director
Head Office Location　　：Otemachi First Square West Tower 1F & 2F, 1-5-1 Otemachi, Chiyoda-ku, Tokyo, LIFORK Otemachi R06

Established　　　　　：September 2014
Business Description　　　：Operation of human resource businesses, including online assistants.
URL　　　　　：https://caster.co.jp

*1: Self-researched based on comparison of the number of companies adopting major domestic remote assistant and online assistant services (April 2025)

*2: Cumulative number of accounts with contract実績 (performance) for services continuously provided by our company.