Interview Count Surges 4x: Why Sairu Re-Introduced Recruitment Support After Once Canceling It? Case Study Released

Caster Inc. (Headquarters: Chiyoda-ku, Tokyo; Representative Director: Shota Nakagawa; hereinafter "Caster") has released a case study where Sairu Inc. (Headquarters: Chuo-ku, Tokyo; President and Representative Director: Kota Kurihara; hereinafter "Sairu"), a consulting firm specializing in new business development and sales/marketing support, re-introduced the recruitment support service "CASTER BIZ recruiting" and achieved stable candidate pool formation and efficient recruitment operations.

Approximately five years ago, Sairu initially adopted CASTER BIZ recruiting during its recruitment infrastructure establishment phase, and once terminated the contract when the necessary recruitment numbers were met. Subsequently, the organization expanded primarily through referral hiring. However, with business growth, the need to stably secure the "volume" and "speed" of recruitment activities increased.
This case study unravels the background behind the re-introduction, which led to a fourfold increase in interviews and the establishment of a "scalable recruitment system" independent of fixed costs.

■ Background of Introduction: Limitations of Referral Hiring and Changes in "Recruitment Challenges" by Phase

Sairu first introduced "CASTER BIZ recruiting" approximately five years ago. At that time, it was used for the purpose of establishing a recruitment foundation, and once switched to in-house operation (primarily referral hiring) when the target was met. However, with further business expansion, they faced the following new challenges:

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

Difficulty in Ensuring Activity Volume: Without a dedicated recruitment specialist, non-core tasks from scouting to scheduling interviews increased the burden on management and the field.

Lack of Reproducibility: A mechanism was needed to consistently maintain contact with candidates, independent of the person-hours of the 담당자.

To address these "phase changes," Sairu decided to re-introduce CASTER BIZ recruiting as a "partner" that could flexibly control the volume and speed of recruitment, rather than just a practical代行.

■ Support Services by "CASTER BIZ recruiting"

• Creation of scout messages and scout sending operations

• Responding to candidate replies, initial contact

• Scheduling casual interviews and formal interviews

• Follow-up for candidates who decline selection

• Sharing casual interview recordings and organizing information

• Organizing selection information and candidate evaluations into text

• Support for organizing and improving overall recruitment operations

■ Results of Introduction

• Eliminated recruitment personalization and standardized operations from candidate pool formation to early selection stages

• Improved reproducibility of recruitment activities by stabilizing scout sending volume and candidate response handling

• Increased the number of casual interviews by approximately four times, from 5-6 per month to over 20 per month

• Reduced recruiter person-hours, establishing a system where they can concentrate on core tasks such as decision-making and strategy design

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

■ Future Development

Caster will continue to support the construction of flexible recruitment systems for growing companies facing challenges such as recruitment resource shortages and personalization of recruitment operations.

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

As a BPaaS partner that establishes recruitment as a continuously revolving mechanism rather than a temporary response, we will accompany companies in their sustainable growth.

■ Click here for the full 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 a series of recruitment tasks from strategy formulation to operation. Based on over 800 cumulative account recruitment support achievements, it logically and efficiently promotes recruitment activities. It frees HR personnel from practical recruitment tasks, providing the experience of "having interviews with desired candidates scheduled just by keeping the calendar open."

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

■ About Caster

Caster, under the mission "Transforming everything about work," supports corporate productivity improvement and sustainable growth with AI x BPaaS. Since its establishment in 2014, it has operated fully remotely company-wide and has supported over 6,000 cumulative accounts (※2) through businesses such as the online assistant "CASTER BIZ" series (No. 1 in introduced companies (※1)). In the AI era, we will lead new ways of working and transform the "world of work" through collaboration between AI and humans.

<Company Profile>

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, LIFORK Otemachi R06, 1-5-1 Otemachi, Chiyoda-ku, Tokyo

Establishment: September 2014
Business Activities: Operation of human resource businesses including online assistants
URL: https://caster.co.jp

※1: Self-researched based on a comparison of the number of companies that have introduced major remote assistant services and online assistant services in Japan (April 2025)

※2: Cumulative number of accounts with contract実績 in continuous provision services operated by our company